WO2022127275A1 - Method and device for model switching, electronic device, and storage medium - Google Patents

Abstract

A method and device for model switching, an electronic device, and a storage medium. The method comprises: displaying multiple first scene models of a target level on a target client, where each first scene model in the multiple first scene models is a levels of detail (LOD) model of one scene object (S202); loading a target stream level to be switched to of the target level, where the target stream level comprises multiple second scene models, and each second scene model in the multiple second scene models is a scene model produced by a model merge of some scene models in the multiple scene models (S204); and while switching to the target stream level, controlling the multiple first scene models to transition by gradient dithering to the multiple second scene models (S206). By means of the method, solved is the problem of poor user visual experience due to visual information jumping found in a model switching scheme in the prior art.

Description

Model switching method and apparatus, electronic device and storage medium

cross reference

This application claims the priority of the Chinese patent application filed on December 16, 2020 with the application number "202011487643.5" and the invention titled "Model Switching Method and Device, Electronic Device and Storage Medium", the entire contents of which are incorporated by reference in in this application.

technical field

The present invention relates to the field of data processing, and in particular, to a model switching method and device, an electronic device and a storage medium.

Background technique

At present, in the process of 3D (3 Dimensions, three-dimensional) game development, the game performance needs to be optimized, and an important process of performance optimization is the rendering optimization of the model. In order to improve the rendering efficiency of the model, LOD (Levels of Detail) can be done on the model, and the model far away from the target character can be switched from the high-end model to the low-end model, and the performance can be improved by rendering a large number of low-end models.

When switching models displayed on a level, there is a problem that the user's visual experience is poor due to the jump of visual information due to the different accuracy of the models before and after switching.

SUMMARY OF THE INVENTION

The present invention proposes the following technical solutions to overcome or at least partially solve or alleviate the above-mentioned problems:

According to an aspect of the present invention, a model switching method is provided, comprising: displaying a plurality of first scene models of a target level on a target client, wherein each first scene in the plurality of first scene models The model is an LOD model of a scene object; load the target flow level to which the target level is to be switched, wherein the target flow level contains multiple second scene models, and each of the multiple second scene models The second scene model is a scene model obtained by merging some of the multiple first scene models; in the process of switching to the target flow level, the multiple first scene models are controlled to pass the gradient The jitter transitions to the plurality of second scene models.

According to another aspect of the present invention, a model switching device is provided, comprising: a display unit for displaying a plurality of first scene models of a target level on a target client, wherein, among the plurality of first scene models Each first scene model is a multi-level of detail LOD model of a scene object; the loading unit is used to load the target flow level to which the target level is to be switched, wherein the target flow level contains a plurality of second scenes model, each second scene model in the plurality of second scene models is a scene model obtained by model merging of some scene models in the plurality of first scene models; the control unit is configured to send the In the process of switching the target flow level, the plurality of first scene models are controlled to transition to the plurality of second scene models through gradual dithering.

According to yet another aspect of the present invention, a computer-readable medium is provided, on which computer programs/instructions are stored, and when the computer programs/instructions are executed by a processor, implement the steps of the above-mentioned model switching method.

According to yet another aspect of the present invention, there is provided a computer apparatus/equipment/system, comprising a memory, a processor and a computer program/instruction stored on the memory, the processor implements the above model when executing the computer program/instruction The steps to switch the method.

According to yet another aspect of the present invention, a computer program product is provided, comprising a computer program/instruction, when the computer program/instruction is executed by a processor, the steps of the above-mentioned model switching method are implemented.

In the embodiment of the present invention, by adopting the mode of model merging and performing model transition through gradient jitter, a plurality of first scene models of the target level are displayed on the target client, wherein each of the plurality of first scene models The first scene model is an LOD model of a scene object; load the target flow level to which the target level is to be switched, wherein the target flow level contains multiple second scene models, and each second scene in the multiple second scene models The model is a scene model obtained by merging some of the multiple first scene models; in the process of switching to the target flow level, the multiple first scene models are controlled to transition to multiple second scene models through gradual dithering , because multiple models are merged into one model, the transition of many-to-one (multiple models to one model) can be realized, the number of submissions of model rendering can be reduced, and the CPU (Central Processing Unit) can be saved while ensuring the model accuracy as much as possible. , central processing unit) and GPU (Graphics Processing Unit, graphics processor) overhead, using gradient jitter for model transition, which can reduce model differences, so as to achieve the purpose of smooth transition of models, to improve the smoothness of model switching, improve The technical effect of the user's visual experience further solves the problem that the user's visual experience is poor due to the jump of visual information in the model switching method in the related art.

Description of drawings

The above and various other advantages and benefits of the present invention will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. In the attached image:

1 is a schematic diagram of a hardware environment of an optional model switching method according to an embodiment of the present application;

2 is a schematic flowchart of an optional model switching method according to an embodiment of the present application;

3 is a schematic diagram of an optional model switching method according to an embodiment of the present application;

4 is a schematic flowchart of another optional model switching method according to an embodiment of the present application;

5 is a structural block diagram of an optional model switching apparatus according to an embodiment of the present application;

6 is a structural block diagram of an optional electronic device according to an embodiment of the present application;

7 is a schematic diagram of a computer apparatus/equipment/system according to an embodiment of the present application;

FIG. 8 is a block diagram of a computer program product according to an embodiment of the present application.

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and specific embodiments. The following description is merely illustrative of the basic principles of the present invention and is not intended to limit it.

First of all, some nouns or terms that appear in the process of describing the embodiments of the present application are suitable for the following explanations:

(1) UE4 (Unreal Engine 4, Unreal Engine 4): is an open source game engine developed by Epic Games;

(2) Streaming Level: Load and unload levels asynchronously while gaming, reducing memory usage and creating a seamless world scene;

(3) HLOD (Hierarchical LOD, Hierarchical Level of Detail): Reduce the memory of the new model by merging models, materials, and textures, and improve rendering efficiency;

(4) StreamingLevelLOD: The solution of streaming LOD is to merge the model material texture by pre-baking the model of the entire map. After the new model is loaded, the original model will be unloaded.

According to an aspect of the embodiments of the present application, a model switching method is provided. Optionally, in this embodiment, the above-mentioned model switching method may be applied to the hardware environment formed by the terminal 102 and the server 104 as shown in FIG. 1 . As shown in FIG. 1 , the server 104 is connected to the terminal 102 through a network, and can be used to provide services (such as game services, application services, etc.) for the terminal or a client (for example, a game client) installed on the terminal. Alternatively, a database may be provided independently of the server for providing data storage services for the server 104 .

The above-mentioned network includes but is not limited to: wired network, wireless network, and the above-mentioned wired network may include but is not limited to: wide area network, metropolitan area network or local area network. The terminal 102 is not limited to a PC (Personal Computer, personal computer), a mobile phone, a tablet computer, or the like.

The model switching method in this embodiment of the present application may be executed by the terminal 102 , may also be executed by the server 104 , or may be executed jointly by the terminal 102 and the server 104 . Wherein, when the terminal 102 executes the model switching method of the embodiment of the present application, it may also be executed by a client installed on the terminal (for example, a client of the target game).

Taking the terminal 102 to perform the model switching method in this embodiment as an example, FIG. 2 is a schematic flowchart of an optional model switching method according to an embodiment of the present application. As shown in FIG. 2 , the process of the method may include: The following steps:

Step S202, displaying multiple first scene models of the target level on the target client, wherein each first scene model in the multiple first scene models is an LOD model of a scene object.

The model switching method in this embodiment can be applied to a game scene (target game scene, such as a big world) spliced by multiple levels, and the game scene can be a game scene of the target game (eg, a three-dimensional game scene).

The target game can be a single-player game or a multi-player game (for example, an open world game); it can be a battle game or a non-combat game (such as a management game); it can be a client game or a For mobile games, the game type of the target game is not limited in this embodiment.

For example, the target game can be an MMORPG (Massive or Massively Multiplayer Online Role-Playing Game), or an AR (Augmented Reality, augmented reality) game, or a VR (Virtual Reality, virtual reality) game , or other types of games.

The terminal device of the target user (target player) may run the target client with the target game application. The target client can communicate with the server, and the above server is the background server of the target game. The target user can log in to the target client running on his terminal device by using the account and password, dynamic password, associated application (third-party application) login, etc., and enter the target game scene (target game map, for example) by operating the target client. , the big world).

Take the big world as an example. A big world is made up of many levels. There are undulating mountains, rivers, and buildings on different levels. The size of a level can be configured as needed, for example, it can be 128×128 meters. of squares (plots), one square next to another, a large world can be made up of many such squares.

In the target game scene, the virtual character controlled by the target user through the target client is the target virtual character. The target game scene may contain multiple levels, and the levels currently displayed on the target client may include the target level. For the target level, when the distance between the target virtual character and the target level is relatively close, multiple first scene models can be displayed on the target level, and each first scene model corresponds to the first scene object in the target level, which is the The LOD model of the object (eg, a multi-level LOD model).

It should be noted that the distance between the target level and the target avatar may be: the distance between the level and the character (for example, the target avatar) is not the distance between an object in the level and the character, but the center of the plot of the level The distance between the point and the person.

The scene objects corresponding to each first scene model may be different, and the types of scene objects corresponding to different first scene models may be the same or different. Scene objects may include, but are not limited to, at least one of the following: buildings, trees, and grass.

For example, the target level contains 3 objects, and the LOD model of each object can be displayed on the currently displayed target level.

According to the number of model faces and details, different levels of LOD models of the same object can correspond to different precisions. The more faces and details, the higher the precision. According to the position and importance of the node of the object model in the scene, the target client can decide the resource allocation for object rendering, that is, which level of LOD model to render.

Step S204, load the target flow level to which the target level is to be switched, wherein the target flow level contains multiple second scene models, and each second scene model in the multiple second scene models is one of the multiple first scene models. The scene model obtained by model merging of part of the scene model.

Since each model has its own multi-level LOD, if the scene model in the scene adopts the multi-level LOD model, when the number of scene models is too large, each model has its own simple model of different LODs and corresponding texture materials. It needs to be rendered separately (rendering a model is called a batch. If there are 1,000 different models in the scene, then 1,000 batches need to be rendered, and they must be rendered separately in a certain order), which cannot guarantee the efficiency and cannot Reduce memory usage.

When the target level is far away from the target character (target virtual character) (for example, exceeding the set distance threshold), it is not necessary to use a high-precision model for the scenery on it. In order to ensure rendering efficiency and reduce content occupancy, it can be replaced It is a low-precision model without affecting the overall effect too much.

In this embodiment, each level in the target game scene (plots with the target size) can be loaded using a streaming loading scheme, so that switching from a high-precision model to a low-precision model can be realized. For each level, one or more streaming levels can be pre-baked for it, that is, StreamingLevelLOD (LOD streaming level). LOD streaming levels (streaming levels) are similar to mesh LODs, can be set according to the streaming distance, and levels can be replaced with corresponding streaming levels.

Streaming Level refers to loading and unloading levels asynchronously during gameplay, which reduces memory usage and creates a seamless world scene. StreamingLevelLOD means: merge the model material texture by pre-baking the model of the entire map, and unload the original model after loading the new model.

When performing a model switching transition, since the data of multiple LOD models in the level are generally placed in the same mesh (mesh), generally only the LOD Dither transition of a single model can be implemented (that is, a 1-to-1 transition). ). If multiple models are baked together, e.g. HLOD, with different LOD data in different meshes, the engine cannot perform many-to-one transitions.

In order to achieve a many-to-one transition and improve the applicability of the model switching method, when the stream level is baked, the scene model in the level can be divided into multiple different parts, and the scene models of different parts can be modeled in different ways. Merge, bake separately into a scene model.

After baking each scene model, the baked model can be composed of a streamer card, or combined with other information to form a streamer level. The baked streaming level can be saved in the server or other storage device, so that it can be loaded into the client (eg, the target client) running the target game when the game is running.

It should be noted that the baked model only bakes the model itself, and does not record the light and shadow information of the model. The lighting is calculated in real time through the material during rendering. For model baking, storing the mesh data of the model is one aspect, and it can also include: storing texture data. For example, if some model rendering requires multiple basic color maps to be mixed, the mixed texture can be calculated directly. Exemplarily, baking the model may include: acquiring mesh information, materials, textures, and the like of the model.

It should be noted that the baking process of streaming levels requires a lot of calculations. In order to improve the smoothness of game running, you can pre-bake scenes or streaming levels through the server. Relative to the running process of the target game, the baking process of the scene can be used as an offline preparation process, rather than being executed when the target game is running.

When the distance between the target virtual character and the target level is relatively far, or when other level switching conditions are satisfied, the target client can determine to switch the target level to the target flow level. The target client can interact with the server to load the target flow level, or directly load a locally saved target flow level.

The target flow level can contain multiple second scene models. Each second scene model in the plurality of second scene models is a scene model obtained by model merging of some scene models in the plurality of first scene models. According to the difference of the corresponding scene objects and the importance of the scene objects, each partial scene model in the plurality of first scene models may be baked by using the same or different baking methods to obtain each second scene model.

For example, the number of scene objects displayed on the target level is 10. When baking the target flow level, you can merge the models of 4 scene objects, bake them into a scene model in the target flow level, merge the models of 3 scene objects, and bake them into a scene in the target flow level Model, merge the remaining 3 scene objects, and bake them into a scene model in the target flow level. After the baking is completed, the number of obtained scene models is 3.

Step S206 , in the process of switching to the target flow level, control the plurality of first scene models to transition to the plurality of second scene models through gradual dithering.

After the loading of the target flow level is completed, the level switching can be performed, and the scene models displayed on the target level are switched from multiple first scene models to multiple second scene models.

In order to prevent the visual information from changing too much when the model is switched, the transition between different models can be performed by means of gradient jitter. For the target level, the target client can control the LOD model on the target level to transition to the corresponding model in the target flow level by means of Dither (jitter, for example, gradient dithering).

It should be noted that gradient dithering refers to: rendering two models at the same time, one renders more and more pixels, and the other renders less and less pixels, so as to switch transitions. The above gradient dithering can be LOD Dither. Dithering (ie, color dithering, color mixing) is the dithering of pixels, which refers to the process of increasing and decreasing pixels.

When the model is switched, the accuracy of the model before and after the switch is different, and the color will also be different. Since the gradient dithering includes the gradient of the color and the change of the model precision, through the gradient dithering, both of them can be made a gradient, so that all the objects on the entire Level can smoothly transition from one model precision to another model precision (for example, from The high-end model transitions to the low-end model) without letting users feel the visual experience of sudden changes in the picture.

For example, as shown in Figure 3, the bucket in Figure 3 has Dither (LOD dithering, an example of dithering) turned on as it transitions from one color (eg, green) to another (eg, yellow), and Instead of transitioning from (a) to (c) all at once, there is a gradient process (b) of color fusion, which is more natural.

Optionally, in this embodiment, in order to identify the first scene model that transitions together, a target material attribute (for example, StreamingLevelDitherLOD) may be added to the model material. When this attribute is activated, the scene model using the model material will enable gradients. The effect of dithering (eg StreamingDitherLOD).

It should be noted that, in this embodiment, the terminal device alone performs flow level switching as an example for illustration. For the server and the client to jointly perform, or the server to perform the data calculation in the target game alone (the client only displays the data synchronized by the server). data), the model switching method in this embodiment is also applicable.

Through the above steps S202 to S206, multiple first scene models of the target level are displayed on the target client, wherein each first scene model in the multiple first scene models is an LOD model of a scene object; load the target The target flow level to which the level is to be switched, wherein the target flow level contains a plurality of second scene models, and each second scene model in the plurality of second scene models is performed for a part of the scene models in the plurality of first scene models. The scene model obtained by model merging; in the process of switching to the target flow level, controlling multiple first scene models to transition to multiple second scene models through gradient jitter, which solves the problem of model switching in the related art due to visual information. The problem of poor user visual experience caused by jumping improves the smoothness of model switching and the user's visual experience.

As an optional embodiment, controlling a plurality of first scene models to transition to a plurality of second scene models through gradual dithering includes:

S11, in the transition time of switching to the target stream level, adjust the jitter parameter corresponding to the target level, and pass the adjusted jitter parameter into the rendering parameter;

S12: Render multiple first scene models and multiple second scene models simultaneously according to the rendering parameters, so as to control the pixels rendered by the multiple first scene models to gradually decrease, and the pixels rendered by the multiple second scene models to gradually increase.

In real-time rendering, after asynchronously loading the LOD level (target stream level), the target client can adjust the jitter parameters corresponding to the target level in real time during the transition time of the stream level, and pass the jitter parameters as parameters to each frame In the rendering parameter of the , the rendering parameters can be used to render multiple first scene models and multiple second scene models at the same time.

DitherFactor can be associated with transition time and can be used to describe how to render different models at the same time. The jitter parameters can be adjusted according to the transition time, that is, at different time points in the transition time, the jitter parameters can be different, so as to control the pixels rendered by multiple first scene models to gradually decrease, and the pixels rendered by multiple second scene models. Pixels gradually increase

For example, after the LOD level is loaded asynchronously, the target client can adjust the DitherFactor (jitter parameter) of the entire level through time transition, and combine all objects (multiple first scene models) of the two levels (target level and target flow level). and multiple second scene models) are rendered at the same time by the dynamic rendering method, and the DitherFactor is passed as a parameter to the shader parameters (rendering parameters) of all objects when rendering each frame.

Through this embodiment, by passing DitherFactor as a parameter into the rendering parameters of all objects in each frame, and rendering all objects in two levels at the same time, the accuracy of model rendering can be ensured, and the smoothness of flow level transition can be improved.

As an optional embodiment, before rendering the multiple first scene models and the multiple second scene models simultaneously according to the rendering parameters, the above method further includes:

S21, acquiring first depth map information of multiple first scene models and second depth map information of multiple second scene models;

S22, filtering object pixels outside the target depth range in the plurality of first scene models according to the first depth map information to obtain a plurality of first target models;

S23, filtering the object pixels outside the target depth range in the plurality of second scene models according to the second depth map information to obtain a plurality of second target models;

The multiple first target models and the multiple second target models are object models to be rendered.

In order to save efficiency on target platforms such as mobile terminal platforms (eg, mobile phone platforms), stencils can be used to filter pixels of different models. For example, objects that do not need to be rendered can be filtered out through depth map information during rendering. pixel.

For multiple first scene models, the target client may acquire first depth map information of the multiple first scene models. For a first scene model, the first depth map information may be used to represent the depth of each pixel in the texture corresponding to the first scene model.

According to the first depth map information, the target client can filter the object pixels in the multiple first scene models that are outside the target depth range. These object pixels are object pixels that do not need to be rendered, so that multiple first target models can be obtained. The plurality of first target models are object models to be rendered.

For multiple second scene models, the target client may acquire second depth map information of the second initial model. For a second image scene model, the second depth map information may be used to represent the depth of each pixel in the texture corresponding to the second scene model.

According to the second depth map information, the target client can filter the object pixels in the multiple first scene models that are outside the target depth range. These object pixels are object pixels that do not need to be rendered, so that multiple second target models can be obtained. The plurality of second target models are object models to be rendered.

With this embodiment, by filtering out the object pixels that do not need to be rendered by using the depth map information during rendering, the resource consumption of rendering can be saved, and the efficiency of model rendering can be improved.

As an optional embodiment, simultaneously rendering multiple first scene models and multiple second scene models according to rendering parameters includes:

S31, according to the rendering parameters, select a model to be rendered corresponding to each pixel point from a plurality of first target models and a plurality of second target models;

S32, rendering the model to be rendered selected for each pixel point on each pixel point.

When rendering each image frame, the target client can select the to-be-received pixel corresponding to each pixel from the plurality of first target models and the plurality of second target models according to the current rendering parameters (including the current jitter parameters). Render the model.

During the transition time from the plurality of first scene models to the plurality of second scene models, the rendering parameters are adjusted over time. When rendering different frames, the model rendered by the same pixel can be different.

Optionally, when rendering, the colors of different models on the same pixel can also be mixed. By adjusting the dither parameter, you can adjust the blending method of each pixel. Other gradient dithering methods may also be used to realize model transition, which is not limited in this embodiment.

With this embodiment, the rendering mode of each pixel is determined according to the rendering parameters, which can improve the smoothness of the model transition.

As an optional embodiment, before loading the target stream level to which the target level is to be switched, the above method further includes:

S41, it is detected that the distance between the target level and the target virtual character is converted from less than the target distance threshold to greater than or equal to the target distance threshold, wherein the target virtual character is a virtual character controlled by the target client.

If the distance between the level and the target character (for example, the target avatar) exceeds the set distance (target distance threshold, the distance is configurable), it can be considered that the distant scenery (the scenery on the level) does not need to use high precision Model, at this time, the high-precision model can be replaced with a low-precision model without affecting the overall display effect too much.

For example, if the distance between the target level and the target virtual character (target character) exceeds the target distance threshold, it can be considered that the scene model in the target level does not need to use a high-precision model, thereby triggering the execution of level switching.

The target client can detect the distance between the target level and the target avatar, and when it detects that the distance between the target level and the target avatar is converted from less than the target distance threshold to greater than or equal to the target distance threshold, determine that it needs to be executed. Level switch, switch the target level to the target flow level. The foregoing detection operation may be performed in real time, or may be performed periodically, which is not limited in this embodiment.

It should be noted that if the distance between the target level and the target virtual character is converted from greater than or equal to the target distance threshold to less than the target distance threshold, the target client can switch the target flow level to the target level again. The switching process is the above process. The reverse process is not repeated in this embodiment.

It should also be noted that if the distance between the target level and the target virtual character is further increased, the flow level switch can be performed again, and the target flow level is switched to another flow level. The model accuracy of the scene model on the flow level can be Lower model accuracy than the scene model on the target flow level.

Through this embodiment, the switching of the streaming level is controlled according to the distance between the level and the character, which can improve the flexibility of switching the streaming level.

As an optional embodiment, before loading the target stream level to which the target level is to be switched, the above method further includes:

S51: Configure the model material of each second scene model in the plurality of second scene models as a target model material, where the target model material has an activated target material attribute, and the target material attribute is used to indicate that the Gradient jitter for model transitions.

In this embodiment, a new material property, that is, a target material property (the property of StreamingLevelDitherLOD) can be added to the model material. When this property is activated, the model using this material will enable the effect of StreamingDitherLOD. The target model material can be a model material with the target material properties activated.

The plurality of first scene models on the target level may be scene models using the material of the target model, and each of the plurality of second scene models on the target flow level may also be scene models using the material of the target model. The scene model using the material of the target model enables the effect of StreamingDitherLOD, so that the model transition can be performed by gradient jitter when switching between streaming levels.

Continued, in this embodiment, the server may configure the model material of the second scene model as a target model material, the target model material is a model material with an activated target material attribute, and the target material attribute may be used to indicate that the flow level is in the flow level. When switching, gradient dithering is used for LOD model transition.

For example, for all objects in the switched streaming level, the material of the above StreamingLevelLODDither can be inherited and enabled.

Through this embodiment, by configuring all objects in the switched streaming level to inherit and enable the material of StreamingLevelLODDither, the smoothness of the streaming level switching can be ensured.

Before loading the target flow level to which the target level is to be switched, the server may bake a plurality of first scene models to obtain the target flow level. For the multiple first scene models, according to different model requirements, different baking methods (for example, at least one baking method) may be used to perform model baking. Different baking methods may be performed sequentially (for example, a specified order, or, for example, the order of model positions in the baking direction), or may be performed in parallel, which is not limited in this embodiment.

As an optional implementation manner, before loading the target stream level to which the target level is to be switched, the above method further includes:

S61, by merging the model vertices, model maps and model materials of the multiple first sub-scene models in the multiple first scene models, bake the multiple first sub-scene models into one scene model to obtain multiple second scene models a scene model.

The multiple first sub-scene models in the multiple first scene models may be iconic objects in the target level, for example, iconic buildings, which need to be rendered intensively (the model accuracy needs to be improved) during level switching.

For multiple first sub-scene models, the server can merge its model vertices, model textures and model materials (or, at least merge model textures), bake multiple first sub-scene models into a new model (new resource), The new model can be a scene model in the target flow level.

It should be noted that the models to be baked by using the above-mentioned merged models, textures, and materials may be one group or multiple groups of models, and each group of models may be baked in the above-mentioned manner. Correspondingly, the number of scene models obtained by combining and baking may be one or more.

It should also be noted that the combined model, texture, and material are used for baking. The baked scene model not only contains the information on the surface of the model, but also contains the information inside the model. The model accuracy can be compared with the model accuracy of the lowest-precision LOD model. quite.

As another optional implementation manner, before loading the target stream level to which the target level is to be switched, the above method further includes:

S62, by performing distance field sampling on the plurality of second sub-scene models in the plurality of first scene models, and baking the plurality of second sub-scene models into one scene model, to obtain a scene model of the plurality of second scene models.

The plurality of second sub-scene models in the plurality of first scene models may be non-iconic buildings in the target level, and do not need to be heavily baked. For multiple second sub-scene models, the server may use a distance field sampling algorithm for baking.

It should be noted that the distance field sampling algorithm is used for baking, and the baked scene model only contains the information of the model surface (sampling is only the sampling of the model surface), and its model accuracy is lower than that of the lowest-precision LOD model.

As another optional implementation manner, before loading the target stream level to which the target level is to be switched to, the above method further includes:

S63, randomly sampling multiple third sub-scene models of the multiple first scene models according to the target sampling accuracy, to obtain multiple sub-models to be baked, wherein the multiple third sub-scene models are the same model;

S64, submit multiple sub-models to be baked according to one batch, bake the multiple sub-models to be baked into one scene model, and obtain a scene model of multiple second scene models, wherein the number of vertices submitted according to one batch is: The number of vertices for a third subscene model.

The plurality of third sub-scene models in the plurality of first scene models may correspond to a large number of identical objects (eg, grass, trees). If the distance between the target level and the target avatar is long, it may not be necessary to render all the multiple third sub-scene models. The server may randomly sample multiple third sub-scene models according to the target sampling accuracy, to obtain multiple sub-models to be baked.

For example, a lawn with 1000 grasses will still be 1000 grasses after normal baking. For rendering efficiency, during the baking process, only 10% or 50% of the grass can be baked with random values, reducing the density of the baked grass and forest.

For multiple sub-models to be baked, the server can submit them in one batch, and the number of vertices submitted in one batch is the number of vertices of a third sub-scene model, so as to bake the multiple sub-models to be baked into one scene model, and obtain The scene model of can be a scene model in the target flow level.

For example, trees, grass, etc. can be baked into the generated Streaming Level by Instance (instantiation). Instance is a way to render a large number of identical objects in a batch. If you only bake the same object into one model, if a model has 100 vertices and an instance contains 10 models, then the baked model has 1000 vertices. If baked into an instance, a batch is still submitted, but only the data of 100 vertices needs to be submitted.

With this embodiment, the scene model is baked in different ways according to different model requirements, which can improve the flexibility of model baking and improve the rendering performance of the model.

As an optional embodiment, after controlling the plurality of first scene models to transition to the plurality of second scene models through gradual dithering, the above method further includes:

S71 , when all the object models in the target flow level have been displayed, uninstall all the object models in the target level.

When switching streaming levels, after the LOD level (target streaming level) is loaded asynchronously, the target client may not unload the currently displayed level first. When the transition time ends, after all the level objects of FadeIn (for example, the scene objects on the target flow level) are all displayed, unload all the level objects of FadeOut (for example, the scene on the target level).

Optionally, in this embodiment, if all the object models in the target flow level have been displayed, the target client can unload all the object models in the target level.

Through this embodiment, after all the level objects of FadeIn are displayed, all level objects of FadeOut are unloaded, which can reduce the memory occupation of the model.

It should be noted that, in this embodiment, the model switching method is described by taking the server execution model baking process and the terminal execution model rendering process as examples. For other baking and rendering execution schemes, the model switching method in this embodiment is The same method applies.

The model switching method in the embodiment of the present application is explained below with reference to optional examples. In this example, LOD Dither (an example of dithering) is done for the way of streaming level loading, to ensure that when switching LODs, all objects on the entire Level can smoothly transition from the high-end model to the low-end model without letting the The user feels that the screen changes suddenly.

As shown in Figure 4, the flow of the model switching method in this optional example may include the following steps:

Step S402 , bake the objects in the level and inherit the material of the StreamingLevelDitherLOD enabled.

The model material can increase the attribute of StreamingLevelDitherLOD (target material attribute). When this attribute is activated, the model using this material will turn on the effect of StreamingDitherLOD. You can bake the objects of the entire level through StreamingLevelLOD, and inherit the material with StreamingLevelLODither turned on. When switching levels, all objects with material properties turned on will have a jitter effect.

Step S404, when switching the flow level, control all objects on the entire Level to transition from the high-end model to the low-end model.

In the process of real-time rendering, when switching the streaming level, after the LOD level is loaded asynchronously, the client can first not unload the currently displayed level, but adjust the DitherFactor that sets the entire level through time transition, and transfer all the two levels Objects are rendered at the same time through the dynamic rendering method, and DitherFactor is passed as a parameter to the shader parameters of all objects every frame. Optionally, on the mobile phone platform, in order to improve efficiency, the pixels of different models can be filtered in a stencil manner.

When the transition time ends and all the level objects of FadeIn are displayed, the client can unload all level objects of FadeOut.

When switching the flow level, the terrain of the entire plot, the houses, trees, grass, etc. on the terrain are all undergoing Dither transitions. In the case of chromatic aberration and deformation between the initial model and the final model, the transition through Dither will be softer.

It should be noted that the model switching method provided in this optional example can be a scheme of combining HLOD (for example, a method of merging models, textures and materials) and Streaming LOD, or a multi-model-to-single-model transition of StreamingLevelLOD Dither The solution is the level-to-level transition solution of Streaming Level LOD Dither, and the transition solution of Streaming Level LOD Dither's Instance (instance) to Instance.

Through this example, it can be guaranteed that when switching LODs, all objects on the entire Level can smoothly transition from the high-end model to the low-end model, making the scene transition more natural.

It should be noted that, for the sake of simple description, the foregoing method embodiments are all expressed as a series of action combinations, but those skilled in the art should know that the present application is not limited by the described action sequence. Because in accordance with the present application, certain steps may be performed in other orders or concurrently. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present application.

From the description of the above embodiments, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is better implementation. Based on this understanding, the technical solutions of the present application can be embodied in the form of software products in essence, or the parts that make contributions to the prior art. The computer software products are stored in a storage medium (such as ROM (Read-Only Memory, ROM). Read-only memory)/RAM (Random Access Memory), magnetic disk, optical disk), including several instructions to make a terminal device (which can be a mobile phone, computer, server, or network device, etc.) The methods described in the various examples are applied.

According to yet another aspect of the embodiments of the present application, a model switching device for implementing the above model switching method is provided. FIG. 5 is a structural block diagram of an optional model switching apparatus according to an embodiment of the present application. As shown in FIG. 5 , the apparatus may include:

A display unit 502, configured to display multiple first scene models of the target level on the target client, wherein each first scene model in the multiple first scene models is an LOD model of a scene object;

The loading unit 504, connected with the display unit 502, is used for loading the target flow level to which the target level is to be switched, wherein the target flow level includes a plurality of second scene models, and each second scene in the plurality of second scene models The model is a scene model obtained by merging some of the scene models in the plurality of first scene models;

The control unit 506, which is connected to the loading unit 504, is configured to control a plurality of first scene models to transition to a plurality of second scene models through gradual dithering during the process of switching to the target flow level.

It should be noted that the display unit 502 in this embodiment can be used to execute the above step S202, the loading unit 504 in this embodiment can be used to execute the above step S204, and the control unit 506 in this embodiment can be used to execute the above step S204. Step S206.

Through the above modules, a plurality of first scene models of the target level are displayed on the target client, wherein each first scene model in the plurality of first scene models is an LOD model of a scene object; load the target level to be switched to The target flow level, wherein the target flow level contains a plurality of second scene models, and each second scene model in the plurality of second scene models is obtained by model merging of some scene models in the plurality of first scene models In the process of switching to the target flow level, multiple first scene models are controlled to transition to multiple second scene models through gradient jitter, which solves the problem of model switching in the related art caused by visual information jumping. The problem of poor user visual experience improves the smoothness of model switching and improves the user's visual experience.

As an optional embodiment, the control unit 506 includes:

The adjustment module is used to adjust the jitter parameters corresponding to the target level during the transition time of switching to the target stream level, and pass the adjusted jitter parameters into the rendering parameters;

The rendering module is used to render multiple first scene models and multiple second scene models simultaneously according to the rendering parameters, so as to control the pixel points rendered by the multiple first scene models to gradually decrease, and the pixels rendered by the multiple second scene models to gradually decrease. Increase.

As an optional embodiment, the above device also includes:

an acquiring unit, configured to acquire first depth map information of multiple first scene models and second depths of multiple second scene models before simultaneously rendering multiple first scene models and multiple second scene models according to the rendering parameters map information;

a first filtering unit, configured to filter object pixels outside the target depth range in the plurality of first scene models according to the first depth map information to obtain a plurality of first target models;

a second filtering unit, configured to filter object pixels outside the target depth range in the plurality of second scene models according to the second depth map information to obtain a plurality of second target models;

Wherein, the plurality of first target models and the plurality of second target models are object models to be rendered.

As an optional embodiment, the rendering module includes:

The selection sub-module is used to select the to-be-rendered model corresponding to each pixel point from a plurality of first target models and a plurality of second target models according to the rendering parameters;

The rendering submodule is used to render the model to be rendered selected for each pixel on each pixel.

As an optional embodiment, the above device also includes:

The detection unit is used to detect that the distance between the target level and the target virtual character is converted from less than the target distance threshold to greater than or equal to the target distance threshold before loading the target flow level to which the target level is to be switched, wherein the target virtual character is The virtual character controlled by the target client.

As an optional embodiment, the above device also includes:

The configuration unit is configured to configure the model material of each second scene model in the plurality of second scene models as the target model material before loading the target stream level to which the target level is to be switched, wherein the target model material has an activated The target material property, which is used to indicate the transition of the model by gradient jitter when the flow level is switched.

As an optional embodiment, the above device also includes at least one of the following:

The first baking unit is used to merge the model vertices, model maps and model materials of the multiple first sub-scene models in the multiple first scene models before loading the target stream level to which the target level is to be switched, and combine the multiple first sub-scene models. The first sub-scene model is baked into a scene model to obtain a scene model of multiple second scene models;

The second baking unit is configured to bake the plurality of second sub-scene models into one scene model by sampling the distance field of the plurality of second sub-scene models in the plurality of first scene models to obtain a plurality of second scene models a scene model of ;

a sampling unit, configured to randomly sample multiple third sub-scene models of the multiple first scene models according to the target sampling accuracy, to obtain multiple sub-models to be baked, wherein the multiple third sub-scene models are the same model; The third baking unit is configured to submit a plurality of sub-models to be baked in one batch, bake the sub-models to be baked into a scene model, and obtain a scene model of the plurality of second scene models, wherein according to a batch The number of vertices submitted is the number of vertices of a third subscene model.

As an optional embodiment, the above device also includes:

The unloading unit is used to unload all the object models in the target level under the condition that all the object models in the target flow level have been displayed after controlling the plurality of first scene models to transition to the plurality of second scene models through gradient jittering .

It should be noted here that the examples and application scenarios implemented by the foregoing modules and corresponding steps are the same, but are not limited to the contents disclosed in the foregoing embodiments. It should be noted that, as a part of the device, the above modules may run in the hardware environment as shown in FIG. 1 , and may be implemented by software or hardware, wherein the hardware environment includes a network environment.

According to yet another aspect of the embodiments of the present application, an electronic device for implementing the above model switching method is also provided, where the electronic device may be a server, a terminal, or a combination thereof.

FIG. 6 is a structural block diagram of an optional electronic device according to an embodiment of the present application. As shown in FIG. 6 , it includes a processor 602, a communication interface 604, a memory 606, and a communication bus 608, wherein the processor 602, the communication interface 604 and the memory 606 communicate with each other through the communication bus 608, wherein,

memory 606 for storing computer programs;

When the processor 602 is used to execute the computer program stored in the memory 606, the following steps are implemented:

S1, displaying multiple first scene models of the target level on the target client, wherein each first scene model in the multiple first scene models is an LOD model of a scene object;

S2, load the target flow level to which the target level is to be switched, wherein the target flow level includes multiple second scene models, and each second scene model in the multiple second scene models is a second scene model in the multiple first scene models The scene model obtained by model merging of some scene models;

S3, in the process of switching to the target flow level, controlling the plurality of first scene models to transition to the plurality of second scene models through gradual dithering.

Optionally, in this embodiment, the above-mentioned communication bus may be a PCI (Peripheral Component Interconnect, Peripheral Component Interconnect Standard) bus, or an EISA (Extended Industry Standard Architecture, Extended Industry Standard Architecture) bus or the like. The communication bus can be divided into an address bus, a data bus, a control bus, and the like. For ease of presentation, only one thick line is used in FIG. 6, but it does not mean that there is only one bus or one type of bus.

The communication interface is used for communication between the above electronic device and other devices.

The memory may include RAM and may also include non-volatile memory, such as at least one disk memory. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

As an example, the above-mentioned memory 606 may include, but is not limited to, the display unit 502 , the loading unit 504 and the control unit 506 in the above-mentioned model switching apparatus. In addition, it may also include but not limited to other modules in the above-mentioned model switching apparatus, which will not be repeated in this example.

The above-mentioned processor can be a general-purpose processor, which can include but is not limited to: CPU, NP (Network Processor, network processor), etc.; can also be DSP (Digital Signal Processing, digital signal processor), ASIC (Application Specific Integrated Circuit, Application-specific integrated circuits), FPGA (Field-Programmable Gate Array, Field Programmable Gate Array) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

Optionally, for specific examples in this embodiment, reference may be made to the examples described in the foregoing embodiments, and details are not described herein again in this embodiment.

Those of ordinary skill in the art can understand that the structure shown in FIG. 6 is for illustration only, and the device implementing the above model switching method may be a terminal device, and the terminal device may be a smart phone (such as an Android phone, an iOS phone, etc.), a tablet computer, a Handheld computers and terminal equipment such as Mobile Internet Devices (MID) and PAD. FIG. 6 does not limit the structure of the above electronic device. For example, the terminal device may also include more or less components than those shown in FIG. 6 (eg, a network interface, a display device, etc.), or have a different configuration than that shown in FIG. 6 .

Those of ordinary skill in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by instructing the hardware related to the terminal device through a program, and the program can be stored in a computer-readable storage medium, and the storage medium can Including: flash disk, ROM, RAM, magnetic disk or CD, etc.

According to yet another aspect of the embodiments of the present application, a storage medium is also provided. Optionally, in this embodiment, the above-mentioned storage medium may be used to execute the program code of any one of the above-mentioned model switching methods in the embodiments of this application.

Optionally, in this embodiment, the foregoing storage medium may be located on at least one network device among multiple network devices in the network shown in the foregoing embodiment.

Optionally, in this embodiment, the storage medium is configured to store program codes for executing the following steps:

S1, displaying multiple first scene models of the target level on the target client, wherein each first scene model in the multiple first scene models is an LOD model of a scene object;

S2, load the target flow level to which the target level is to be switched, wherein the target flow level includes multiple second scene models, and each second scene model in the multiple second scene models is a second scene model in the multiple first scene models The scene model obtained by model merging of some scene models;

S3, in the process of switching to the target flow level, controlling the plurality of first scene models to transition to the plurality of second scene models through gradual dithering.

Optionally, for specific examples in this embodiment, reference may be made to the examples described in the foregoing embodiments, which will not be repeated in this embodiment.

Optionally, in this embodiment, the above-mentioned storage medium may include, but is not limited to: U disk, ROM, RAM, removable hard disk, magnetic disk, or optical disk, and other mediums that can store program codes.

The above-mentioned serial numbers of the embodiments of the present application are only for description, and do not represent the advantages or disadvantages of the embodiments.

If the integrated units in the above-mentioned embodiments are implemented in the form of software functional units and sold or used as independent products, they may be stored in the above-mentioned computer-readable storage medium. Based on this understanding, the technical solution of the present application can be embodied in the form of a software product in essence, or the part that contributes to the prior art, or all or part of the technical solution, and the computer software product is stored in a storage medium, Several instructions are included to cause one or more computer devices (which may be personal computers, servers, or network devices, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application.

In the above-mentioned embodiments of the present application, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments.

In the several embodiments provided in this application, it should be understood that the disclosed client may be implemented in other manners. The apparatus embodiments described above are only illustrative, for example, the division of the units is only a logical function division, and there may be other division methods in actual implementation, for example, multiple units or components may be combined or Integration into another system, or some features can be ignored, or not implemented. On the other hand, the shown or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, indirect coupling or communication connection of units or modules, and may be in electrical or other forms.

The units described as separate components may or may not be physically separated, and components displayed as units may or may not be physical units, that is, may be located in one place or distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution provided in this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit. The above-mentioned integrated units may be implemented in the form of hardware, or may be implemented in the form of software functional units.

The above are only the preferred embodiments of the present application. It should be pointed out that for those skilled in the art, without departing from the principles of the present application, several improvements and modifications can also be made. It should be regarded as the protection scope of this application.

Various component embodiments of the present invention may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art should understand that a microprocessor or a digital signal processor (DSP) may be used in practice to implement some or all functions of some or all components in the model switching apparatus according to the embodiment of the present invention. The present invention can also be implemented as a program/instruction (eg, computer program/instruction and computer program product) for an apparatus or apparatus for performing some or all of the methods described herein. Such programs/instructions implementing the present invention may be stored on a computer readable medium, or may exist in the form of one or more signals, such signals may be downloaded from an Internet website, or provided on a carrier signal, or in any form Available in other formats.

Computer-readable media includes both persistent and non-permanent, removable and non-removable media, and storage of information may be implemented by any method or technology. Information may be computer readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read only memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), Flash Memory or other memory technology, Compact Disc Read Only Memory (CD-ROM), Digital Versatile Disc (DVD) or other optical storage, Magnetic tape cartridges, disk storage, quantum memory, graphene-based storage media or other magnetic storage devices or any other non-transmission media can be used to store information that can be accessed by computing devices.

FIG. 7 schematically shows a computer apparatus/device/system that can implement a model switching method according to the present invention, the computer apparatus/device/system including a processor 710 and a computer-readable medium in the form of a memory 720 . Memory 720 is an example of a computer-readable medium having storage space 730 for storing computer programs/instructions 731 . When the computer program/instructions 731 are executed by the processor 710, various steps in a model switching method described above can be implemented.

Figure 8 schematically shows a block diagram of a computer program product implementing the method according to the invention. The computer program product includes a computer program/instructions 810 that, when executed by a processor, such as the processor 710 shown in FIG. 7, can implement a model switching method described above in each step.

Specific embodiments of this specification have been described above, and other embodiments are intended to be included within the scope of the appended claims. In some cases, the actions or steps recited in the claims can be performed in an order different from that in the embodiments and still achieve desirable results. Additionally, the processes depicted in the figures do not necessarily follow the specific order shown, or sequential order, to achieve desirable results. In certain embodiments, multitasking and parallel processing are also possible or advantageous.

It should also be noted that the terms "comprising", "comprising" or any other variation thereof are intended to encompass a non-exclusive inclusion such that a process, method, article or device comprising a series of elements includes not only those elements, but also Other elements not expressly listed, or which are inherent to such a process, method, article of manufacture, or apparatus are also included. Without further limitation, an element qualified by the phrase "comprising a..." does not preclude the presence of additional identical elements in the process, method, article of manufacture, or device that includes the element.

It should be understood that the above-mentioned embodiments are only for the purpose of illustrating the present invention and not for limiting the present invention. Those skilled in the art can also implement the present invention in other ways without departing from the basic spirit and characteristics of the present invention. The scope of the present invention shall be determined by the appended claims, and any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of one or more embodiments of this specification shall be covered therein.

Claims (12)

1. A model switching method, comprising:

   Displaying a plurality of first scene models of the target level on the target client, wherein each first scene model in the plurality of first scene models is a multi-level of detail LOD model of a scene object;

   Load the target flow level to which the target level is to be switched, wherein the target flow level contains multiple second scene models, and each second scene model in the multiple second scene models is the multiple second scene models A scene model obtained by merging some of the scene models in the first scene model;

   In the process of switching to the target flow level, the plurality of first scene models are controlled to transition to the plurality of second scene models through gradual dithering.
2. The method according to claim 1, wherein controlling the plurality of first scene models to transition to the plurality of second scene models through gradual dithering comprises:

   During the transition time of switching to the target flow level, adjust the jitter parameter corresponding to the target level, and pass the adjusted jitter parameter into the rendering parameter;

   The multiple first scene models and the multiple second scene models are simultaneously rendered according to the rendering parameters, so as to control the pixels rendered by the multiple first scene models to gradually decrease, and the multiple second scene models Rendered pixels gradually increase.
3. The method according to claim 2, wherein before rendering the plurality of first scene models and the plurality of second scene models simultaneously according to the rendering parameters, the method further comprises:

   acquiring first depth map information of the multiple first scene models and second depth map information of the multiple second scene models;

   Filter object pixels outside the target depth range in the plurality of first scene models according to the first depth map information to obtain a plurality of first target models;

   Filter object pixels outside the target depth range in the plurality of second scene models according to the second depth map information to obtain a plurality of second target models;

   Wherein, the plurality of first target models and the plurality of second target models are object models to be rendered.
4. The method according to claim 3, wherein rendering the plurality of first scene models and the plurality of second scene models simultaneously according to the rendering parameters comprises:

   According to the rendering parameters, the to-be-rendered model corresponding to each pixel is selected from the plurality of first target models and the plurality of second target models;

   The to-be-rendered model selected for the respective pixel points is rendered on the respective pixel points.
5. The method according to claim 1, wherein before loading the target flow level to which the target level is to be switched, the method further comprises:

   It is detected that the distance between the target level and the target virtual character is converted from less than a target distance threshold to greater than or equal to the target distance threshold, wherein the target virtual character is a virtual character controlled by the target client.
6. The method according to claim 1, wherein before loading the target flow level to which the target level is to be switched, the method further comprises:

   The model material of each second scene model in the plurality of second scene models is configured as a target model material, wherein the target model material has an activated target material attribute, and the target material attribute is used to indicate that the flow Model transition through gradient jitter when switching levels.
7. The method according to claim 1, wherein before loading the target flow level to which the target level is to be switched, the method further comprises one of the following:

   By merging model vertices, model maps and model materials of multiple first sub-scene models in the multiple first scene models, and baking the multiple first sub-scene models into one scene model, the multiple first sub-scene models are obtained. a scene model of the second scene model;

   By performing distance field sampling on a plurality of second sub-scene models in the plurality of first scene models, and baking the plurality of second sub-scene models into one scene model, the results of the plurality of second scene models are obtained. a scene model;

   Randomly sample multiple third sub-scene models of the multiple first scene models according to the target sampling accuracy to obtain multiple sub-models to be baked, wherein the multiple third sub-scene models are the same model; Submit the plurality of sub-models to be baked in one batch, bake the plurality of sub-models to be baked into a scene model, and obtain a scene model of the plurality of second scene models. The number of vertices is the number of vertices of one of the third sub-scene models.
8. The method according to any one of claims 1 to 7, wherein after the controlling the plurality of first scene models to transition to the plurality of second scene models through gradual dithering, the method further comprises: include:

   Under the condition that all object models in the target flow level have been displayed, all object models in the target level are unloaded.
9. A model switching device, characterized in that it includes:

   a display unit, configured to display multiple first scene models of the target level on the target client, wherein each first scene model in the multiple first scene models is a multi-level of detail LOD model of a scene object;

   A loading unit, configured to load a target flow level to which the target level is to be switched, wherein the target flow level includes a plurality of second scene models, and each second scene model in the plurality of second scene models a scene model obtained by model merging for part of the scene models in the plurality of first scene models;

   The control unit is configured to control the plurality of first scene models to transition to the plurality of second scene models through gradual dithering during the process of switching to the target flow level.
10. A computer device/device/system, comprising a memory, a processor, and a computer program/instruction stored on the memory, the processor implementing the computer program/instruction according to any one of claims 1-8 when the processor executes the computer program/instruction steps of the method.
11. A computer-readable medium having stored thereon computer programs/instructions which, when executed by a processor, implement the steps of the method according to any one of claims 1-8.
12. A computer program product comprising computer programs/instructions which, when executed by a processor, implement the steps of the method according to any one of claims 1-8.

Images