JPH04362786A - Picture processing method and device - Google Patents

Abstract

PURPOSE:To easily generate complicated curved surfaces changing continuously. CONSTITUTION:A storage means storing curved surfaces information on a basic graphic, a displacing quantity generation means generating continuous displacing quantity for a two-dimensional area, curved surfaces information generation means 1 generating new curved surfaces information by displacing a point on a graphic printed by a mapping to this graphic from the said area based on the displacing position for each point of the area and a display means 3 displaying a graphic based on the curved surfaces information generated by the curved surfaces information generation means 1.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to an image processing method,
Particularly in computer graphics, the present invention relates to a method of generating a curved surface in which a curved surface constituting an original surface is locally transformed into a new curved surface.

0002

[Prior Art] Conventionally, in computer graphics, as a method for generating three-dimensional curved surfaces, data for basic curved surfaces such as cylinders and spheres (these are called primitive curved surfaces) are prepared in advance. You can create a new surface by combining primitive surfaces as needed, or you can specify points on the newly created surface as control points and create a surface that passes through these control points using a spline function. Methods such as interpolation are used.

Even when creating a curved surface using this spline function, it is actually necessary to set a large number of control points, so in order to form a large number of control points, a primitive curved surface is used or By combining , sectional views, etc., control points are set within a practically acceptable range. Therefore, in practical terms, this case also has the same characteristics as the case where primitive curved surfaces are combined.

Therefore, these conventional methods actually use the external shape of a primitive curved surface as a basic shape, and attempt to obtain a desired curved surface by deforming the curved surface based on this basic shape. It is believed that it is possible to create a curved surface that is practically satisfactory as long as it is applied to express the external shape of a mechanical object.

[0005]

[Problem to be Solved by the Invention] However, for example, a curved surface representing a human face must be expressed by a curved surface that gives a soft impression and is different from a primitive curved surface (this is called a free-form surface). When trying to create a natural-looking curved surface, conventional surface creation methods are strongly influenced by the characteristics of primitive surfaces.
I can't say it's enough.

[0006] Furthermore, even if conventional curved surface creation methods are applied to animation creation devices and special effects devices, it may not be possible to obtain smooth curved surface deformation, and the applicable curved surface deformation patterns are limited to a narrow range. It also has the disadvantage of being limited to

The present invention has been made in consideration of the above points, and provides a method for creating a curved surface that can create various curved surfaces from primitive curved surfaces and easily obtain a continuously changing curved surface. This is what we propose.

[0008]

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a storage means for storing curved surface information of a basic figure, and a displacement amount that generates a continuous displacement amount for a two-dimensional area. and curved surface information generating means for generating new curved surface information by displacing points on the figure that are mapped from the area to the figure based on the amount of displacement for each point in the area. , display means for displaying a figure based on the curved surface information generated by the curved surface information generating means.

[0009]

EXAMPLES (Explanation of Principle) First, the principle of the present invention will be explained. According to the present invention, information on a free-form surface is obtained as the sum of values of mutually associated positions of two pieces of curved surface information shown in FIGS. 1 and 2 to 4, respectively.

FIG. 1 is a diagram showing a cylindrical primitive. Under conditions expressed in a cylindrical coordinate system, attention is paid to one point A (ra, θa, ha) on the cylindrical surface. 2 to 4 are another type of curved surface information, which is expressed in a three-dimensional orthogonal coordinate system. For convenience, the radial direction of the cylinder coordinates is referred to as the r coordinate, the direction of the circumferential angle as the θ coordinate, and the height direction of the cylinder as the h coordinate. Let the orthogonal coordinates be the x, y, and z coordinates. Now, as shown in FIG. 2, the xy plane is associated with the θ-h plane (the surface of the body of the cylinder) of the cylindrical coordinate system. 2 will then be mapped onto the side surface of the cylinder in FIG. 1. At this time, if the z value of each position on the xy plane is determined as shown in FIGS. 3 and 4, the side surface of the cylinder that is mapped will be
The value is expressed as data Δ showing the ups and downs from the cylindrical surface shown in Figure 1.
By using it as r, a deformed curved surface as shown in FIG. 5 is obtained. Let one point on the cylindrical surface P1 in FIG. 1 be A(ra, θa, ha), and the corresponding θ−h(
If one point on the (x-y) plane is a(θa, ha) and its Z value is Δra, the result is one point A'(ra+Δr
a, θa, ha).

[0011] Here, the corresponding points between the two primitive curved surfaces can be determined as follows.

All primitive curved surfaces used as a curved surface database are divided into a fixed number of grids, regardless of the shape of the curved surface, as shown in FIGS. 6 to 8, for example. The grids can be associated with each other while maintaining their connectivity. 4 points in each of Figures 6 to 8, B, C,
D and E indicate corresponding points on each curved surface.

In the examples shown in FIGS. 2 to 4, the displacement data is

[0014]

[Outside 1] That is, a displacement distribution having a Gaussian distribution with a maximum height Δr0 centered at (θ0, h0) is taken. A position having a displacement amount of Δr0×(1/e) (here, e is the base of the natural logarithm) is an ellipse with a major axis of 2l and a minor axis of 2s. Therefore, in FIG. 5, the side surface of the cylinder has a curved surface with a Gaussian distribution.

[0015] Conversely,

[0016]

[Outside 2] By taking this, it is possible to realize a Gaussian distribution of indentations.

(Embodiment of curved surface creation device) The above-described curved surface creation method can be realized by a curved surface creation device configured as shown in FIG.

In FIG. 9, reference numeral 1 denotes a computer-configured curved surface calculation device, which converts primitives and shape position information shown by equations 1 and 2 into video signals by a curved surface display control device 2, and then displays the cathode ray tube structure. Display on device 3.

Further, the curved surface calculation device 1 is shown in FIGS. 12 and 13.
The processing procedure shown in the flowchart, data for displaying primitives, arithmetic expressions such as Equation 1 and Equation 2, and data such as various default values are stored in memory, and further,
Parameters input and set by the operator can also be stored in the memory, and the CPU uses these data to execute calculations and various controls.

The surface calculation device 1 inputs instructions for primitives that are the basis of shape formation, amounts of deformation, and parameters necessary for calculating Equations 1 and 2 using a mouse 4 and a mouse 4 in accordance with the display on the display device 3. The configuration is such that the keyboard 5 is used.

[0021] To select a primitive as a base for forming a shape, for example, as shown in FIG. This is done by moving the cursor and clicking the mouse button on the desired primitive.

Next, as a method of deformation, as shown in FIG. The transformation (operation) to be executed from the cursor is selected using the mouse 4 in the same way as primitive selection.

For the amount of deformation shown by Equations 1 and 2, for example, as shown in FIG. 10, values for setting the area to which the deformation is applied are input according to the display on the display device 3. Figure 10
In this display, the right side of the screen is used as an operation area for setting various values, and the remaining area is used as a display area for the set values. In Equations 1 and 2, s is called the horizontal direction, and l is called the vertical direction, and in both directions, there are three predetermined selection values: wide, normal, and narrow set values SW, SO, SN; lW, lO
, IN and determine the approximate value. Further, by increasing or decreasing this value in small increments as a fine adjustment operation, it is possible to make small corrections.

The center position of the deformation can be determined by moving the cursor with the mouse 4 on the original figure displayed in the figure display area as shown in FIGS. 9 and 10 and pressing down the mouse button. The point corresponding to becomes the center of the deformation distribution. Furthermore, if you move the mouse while holding down the mouse button, the amount of deformation Δr will change depending on the amount of movement.
0 is determined.

Such a deformation operation is obtained by the curved surface calculation device 1 using its CPU to execute the processing procedures shown in FIGS. 12 and 13, which will be described below, and which are stored in the memory.

[0026] The CPU of the surface calculation device 1 performs step S1.
After starting the processing procedure in step S2
Among the various values used in the process, values (default values) to be used when no clear instructions are given by the operator are set, and the memory, pointer, etc. to be used are initialized. In step S3, it is possible to change the temporarily set viewpoint position. When changing the viewpoint position, the user issues an instruction using the mouse 4 and inputs the viewpoint position using the mouse 4 or the keyboard 5. In step S4, as shown in FIG. 11, a list of basic shapes prepared in advance in the apparatus is displayed on the display device 3, and a basic shape (original curved surface) is selected and input using the mouse 4. In step S5, as described with reference to FIG. 9, the types of basic transformation calculations prepared in advance in the device are displayed on the display device 3, and the mouse 4 is used to select the type of transformation calculation. In step S6, it is determined whether the operation selected in step S5 does not change the basic shape itself, but changes a part of the surface shape of the basic shape (original curved surface). . In the case of changes to the basic shape itself, such as topknots (for example, changing a cylindrical shape to a horse-shaped one) or elongation (changing a thick and short cylinder to a thin and long one),
Various processing routine steps S17 corresponding to each
is executed, and the process proceeds to step S9 to display the curved surface of the shape generated as a result. On the other hand, if the calculation of pulling or recessing is instructed, the process advances to step S7. In step S7, the size of the deformation area is designated using the mouse 4, as described with reference to FIG. In step S8, the center position and amount of deformation are specified using the mouse 4 based on the displayed shape data as shown on the left side of the display screen in FIG. In step S9, data of a deformed surface is calculated and output from the input basic shape and information on the type of deformation calculation, deformation position, and amount of deformation. Step S
10, the transformed curved surface data calculated in step S9 is sent to the display device 3 via the curved surface display control device 2.
to be displayed.

In this state, the CP of the surface calculation device 1
U is connected to the curved display control device 2 and the display device 3,
By continuing to display the curved surface data after deformation, in the next step S11, the operator can check whether the degree of deformation is appropriate to the operator's requirements while looking at the display on the display device 3. . Thereafter, the CPU moves to the next step S12 and determines whether the operator has requested further correction or termination of the process. Here, if a signal requesting further correction is input, the surface calculation device 1
The CPU returns to step S3 described above and returns to a state where it waits for new parameter settings.

[0028] At this time, the operator performs steps S3 to S5 and S7.
, 8, the calculation of the deformation calculation formula is re-executed in steps S9 to 10, the deformed curved surface is displayed on the display device 3, and step S
At step 11, the operator is again asked to judge whether the deformation is as desired.

In this manner, the CPU of the curved surface calculation device 1 is able to repeat generation of the curved surface by the loop of steps S3 to S12 until the operator achieves the transformation that meets his/her requirements. Eventually, when the operator is able to make the settings to his satisfaction, he determines that no further correction is necessary and inputs a termination signal to the surface calculation device 1, whereupon the CPU of the surface calculation device 1 moves to step S13 and completes the settings. store the data, the type of primitive, the size of the deformation area, the center position of deformation, and the size of deformation in the position indicated by the counter of the data memory table in the shape data memory area in the curved surface calculation device 1;
Count up the counter. Next, in step S15, the operator waits for a determination as to whether or not to generate the next curved surface data.
When creating the next data, the process returns to step S3. When finished,
Proceeding to step S16, the series of processing ends.

(Embodiment 2) In the above embodiment, if it is determined in step S12 that correction is required and the process returns to step S3, steps S3 to S5, 7, and 8 are not necessarily all reset. It is not necessary, and a method may be used in which the state immediately before returning to step S3 is held and modifications are added to that state. In this case, the displacement amount is added to the state immediately before returning to step S3 and used as new displacement amount data. FIG. 14 illustrates this state. Create 6 and 7 using the pull operation, and 8 using the indentation operation. The center of pull 6 is set as point F, the center of pull 7 is set as point G, and the center of pull 8 is set as point H. If the basic shape is set to a cylinder, the displayed shape will be as shown in FIG. 15.

In this case, the processing procedure can be expressed similarly to the flowcharts shown in FIGS. 12 and 13. However, as mentioned above, steps S3 to S5, 7, and 8 are
The configuration is such that the state immediately before returning to can be followed as it is, and the displacement amount is added one after another, and the parameters of each displacement amount data are held. In the calculation in step S9, the sum of the plurality of displacement amounts is used as the display curved surface data as the displacement amount of the curved surface at each point. That is,

[0032]

[Example 3] Here, Δr (θ, h) is (θ, h) of the basic shape surface
Δri(θ, h) represents the amount of change on (θ, h) of the basic shape surface determined from the i-th parameter of a plurality of displacement data. Also, step S1
In step 3, when setting the parameters, the number of plural pieces of displacement data and the parameters of the displacement data may be held. By making it possible to create displacement data using multiple pieces of displacement data in this way, more complex curved surfaces can be created with simple calculations, and operations can be performed interactively, as if working with clay on a display device. This has the effect of making it possible.

[0033]

As described above, according to the present invention, a partial region of a curved surface before deformation is specified, a displacement amount is determined,
By associating this displacement amount surface with the original curved surface to form a deformed surface, it is possible to actually generate a deformed surface in real time, and also to use the curved surface as a parameter. Parameter setting operations can be done intuitively and interactively because you can use things that can be set while looking at them, such as the position of the point of action, the size of the deformation area, the amount of deformation, and the direction. be.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of basic figures.

FIG. 2 is a diagram showing displacement data.

FIG. 3 is a diagram showing displacement data.

FIG. 4 is a diagram showing displacement data.

FIG. 5 is a diagram showing an example of a deformed figure.

FIG. 6 is a diagram showing the correspondence between basic figures and displacement data.

FIG. 7 is a diagram showing the correspondence between basic figures and displacement data.

FIG. 8 is a diagram showing the correspondence between basic figures and displacement data.

FIG. 9 is a block diagram showing an embodiment of the device of the present invention.

FIG. 10 is a diagram showing an example of a display screen.

FIG. 11 is a diagram showing an example of a display screen.

FIG. 12 is a flowchart showing the operation of the embodiment.

FIG. 13 is a flowchart showing the operation of the embodiment.

FIG. 14 is a diagram showing displacement data.

FIG. 15 is a diagram showing an example of a deformed figure.

[Explanation of symbols]

1 Surface calculation device 2 Curved surface display control device 3 Display device 4 Mouse 5 Keyboard

Claims (2)

[Claims] [Claim 1] Store curved surface information of a basic figure,
By generating a continuous displacement amount for a two-dimensional area, and displacing a point on the figure that is mapped from the area to the figure based on the displacement amount for each point in the area, An image processing method characterized by generating new curved surface information and displaying a figure based on the generated curved surface information. 2. Storage means for storing curved surface information of a basic figure; displacement amount generation means for generating a continuous displacement amount for a two-dimensional area; curved surface information generating means for generating new curved surface information by displacing points on the graphic that are mapped from the region to the graphic; An image processing device comprising: display means for displaying.