FR3025645A1 - METHOD FOR DISPLAYING AND ADJUSTING THE ORIENTATION OF A VIRTUAL IMAGE FOR A NOMADIC ELECTRONIC DISPLAY DEVICE - Google Patents

Abstract

Method for displaying and adjusting the orientation of a virtual view for a nomadic electronic display device comprising at least one screen for displaying the virtual view and a device for detecting the angular position (α) of the device display relative to a substantially vertical axis with respect to the ground passing through the center of gravity of the display device, in which the orientation of the displayed virtual view and the distance between the electronic display device and a predetermined point of interest as a function of the angular position (α) of the display device.

Description

The present invention concerns methods for displaying and adjusting the orientation of an image or virtual view, for example a map or an image of a video game or any image, used on any means of displaying the virtual view, such as a nomadic electronic display device, for example a mobile phone or a digital tablet. Today, electronic display devices offer numerous applications for providing three-dimensional virtual information in order to get closer to reality, particularly in the field of cartographies to find their way more easily in space or in the field of television applications.

Some electronic display devices require the use of specialized glasses or shadows and special effects that make you think of a three-dimensional image. However, changing the orientation, the position of the display screen, and the brightness are usually not realistically updated on the display screen, so that the virtual image is strongly degraded compared to the real image. The advent of online mapping services, the democratization of nomadic electronic display devices with geolocation functions and the deployment of mobile internet have led to the creation of navigation tools allowing easy navigation by displaying plans. user-centric. Most mobile mapping applications use gyro sensors and a geolocation function to center the virtual view on the user's position as well as a compass function in order to properly orient the virtual view with respect to the object. 'user. This makes it possible to recalibrate the cartography with respect to the user and thus to minimize the mental load necessary for the user to establish a correspondence between the virtual cartography appearing on the screen and the real environment around the user. Nowadays, it is possible to transform the plans, generally initially displayed in two dimensions, into three dimensions in order to display the infrastructures in perspective and thus to be more easily identified. However, the transition from the two-dimensional view mode to the three-dimensional view mode is manual and requires the intervention of the user, for example by a tactile gesture on the screen of the nomadic electronic display device, for example. for example by sliding two fingers to change the inclination of the virtual view or by spreading two fingers to zoom in on a point of interest. Reference can be made to US 2013/0016102 which discloses a three-dimensional simulator of objects comprising a device for adjusting the display as a function of the position and orientation of the user's head picked up by a sensor. image, more precisely according to the point of view of the user, in order to generate an angle of view of the three-dimensional image appropriate for the user. However, the use of an image sensor to capture the user's point of view is particularly expensive and requires integration from the manufacturing of the display device. The present invention aims to improve the methods of displaying a virtual image by reinforcing the correspondence between the real image and the virtual image displayed on the screen of a nomadic electronic display device.

The invention also aims to provide an intuitive means for moving from a virtual image in two dimensions to a virtual image in three dimensions and more particularly in the display area of the maps.

The invention proposes a method for displaying and adjusting the orientation of a virtual view for a nomadic electronic display device comprising at least one screen for displaying the virtual view and a device for detecting the virtual view. angular position of the display device with respect to a substantially vertical axis with respect to the ground passing through the center of gravity of the display device. The display method includes a step of adjusting the orientation of the displayed virtual view and the distance between the electronic display device and a predetermined point of interest as a function of the angular position of the display device. Thus, by varying the angular position of the nomadic electronic display device, that is to say the angle between the axis perpendicular to the electronic display device and the vertical axis 15 passing through its center of gravity, one rule the orientation of the displayed virtual view as well as the distance between the electronic display device and the point of interest. In other words, the two-dimensional allocentric view is shifted to a three-dimensional egocentric view smoothly, smoothly, to provide a continuous transition between the views. Note that such a display method can be used to display maps, but also to display any image, for example, during a video game application. Advantageously, the display method comprises a measurement step 25 by the device for detecting the angular position, the angle between a straight line, perpendicular to the display device and passing through its center of gravity and the vertical line and at the least one step of comparing the angle with at least one threshold value. In one embodiment, a calibration value of the threshold values is set. The calibration value may be for example 30 °. Thus, the transition between the virtual views applies in an angular range defined by the threshold value, which makes it possible not to trigger the transition at inconvenient moments, for example when the user observes the plan and when he does not want the view to move with every slight movement of his hand. In one embodiment, when the angle between the two lines defined above is less than or equal to a first threshold value increased by the calibration value, the angle of the virtual view is oriented towards a two-dimensional view. dimensions and the display device is moved away from the point of interest. When the angle between the two straight lines defined above is greater than the first threshold value increased by the calibration value, a second step of comparing the angle between the two lines with a second threshold value is carried out. , taking into account the calibration value. In one embodiment, when the angle between the two lines defined above is less than the second threshold value minus the calibration value, the angle of the virtual view is oriented proportionally to the angular position of the device. display and the display device is brought closer to the point of interest. When the angle between the two straight lines defined above is greater than or equal to the second threshold value minus the calibration value, the angle of the virtual view is oriented towards a three-dimensional view and the device is centered. display on the point of interest. The first threshold value is, for example, equal to 0 °, the second threshold value is, for example, equal to 90 ° and the calibration value is, for example, between 0 ° and 30 °. The angular position detecting device may be a gyro sensor or an accelerometer. In one embodiment, the electronic display device comprises a device for geographic location or geolocation. By geographical location device or geolocation means any means for determining the geographical position of the mobile device from the radio waves they emit. In one embodiment, the electronic display device includes a North Magnetic Direction Indicator. Means of indication of the magnetic north direction such as a magnetometer or a compass. Due to the geographical location device and / or the magnetic north direction indicating device, the virtual view is closer to the actual view. The predetermined point of interest can be determined manually or automatically by using the geographical position of the nomadic display device determined by the geographic location device or geolocation and by the magnetic north direction indicating device. According to a second aspect, the invention relates to a nomadic electronic display device comprising at least one display screen of a virtual view and a device for detecting the angular position of the display device with respect to an axis 15 substantially vertical to the ground passing through the center of gravity of the display device and a display processing system implementing the display method as described above. Other objects, features and advantages of the invention will become apparent on reading the following description, given solely by way of nonlimiting example, and with reference to the appended drawings, in which: FIG. schematically, the steps of the display method according to the invention; FIG. 2 illustrates a display device comprising the display method according to the invention; FIGS. 3A and 3B respectively represent the display device in a first angular position and the corresponding virtual view perceived by the user; FIGS. 4A and 4B respectively represent the display device in a second angular position and the corresponding virtual view perceived by the user; and FIGS. 5A and 5B respectively represent the display device in a third angular position and the corresponding virtual view perceived by the user. As illustrated in FIG. 1, the method for displaying and adjusting the orientation of an image or virtual view is intended to be integrated in a nomadic electronic display device 1 illustrated schematically in FIG. Nomadic electronic display device means a mobile phone, a digital tablet, an electronic slate, or more generally all electronic objects having a surface intended to be viewed, read, viewed or modified by a user. In general, at least one zone of the surface of the portable electronic display device comprises a screen and / or a touch pad intended to be touched by the finger or by a stylus adapted for this purpose by the user. The surface 15 may also include buttons or the like intended to be touched or manipulated by the user. As illustrated in FIG. 2, the portable electronic display device 1 comprises a device 2 for detecting the angular position a of the display device 1 with respect to an axis 20 that is substantially vertical with respect to the ground passing through the center. The device for detecting the angular position may be, for example, a gyro sensor or an accelerometer. The electronic display device 1 may, by way of non-limiting example, comprise a camera (not shown), a device 3 for geographical location or geolocation and / or a device 4 for indicating the direction of the magnetic north. The electronic display device 1 comprises a display processing system 5 implementing the display method illustrated in FIG. 1 and communicating with a display screen 6 and a means 7 for storing the information provided by 5. As shown in FIG. 1, the display method comprises a first step 10 of starting the display method and a second step 15 of determining the point of the display. interest P on which the virtual camera of the display device 1 must center. The step of determining the point of interest P can be carried out manually by the user, for example by entering coordinates or an address, or automatically by using the geographical position of the nomadic display device 1 determined by the device. 3 of geographic location or geolocation and the device 4 for indicating the direction of magnetic north. Once the point of interest P is determined, the display method proceeds, in step 20, to the measurement by the device 2 for detecting the angular position of the angle α between a line a, visible in FIGS. 3 to 5, perpendicular to the display device 1 and passing through its center of gravity G and a straight line A, visible in FIGS. 3 to 5, substantially vertical and passing through the center of gravity 15 G of the device of FIG. The angle α is then compared, in step 30, with a first threshold value S1, taking into account a manually adjustable calibration value Cal. By way of example, the first threshold value Si can be set at 0 ° and the calibration value Cal can be set at 30 °.

Thus, if the angle a is less than or equal to the first threshold value Si increased by the calibration value Cal, that is a <Si + Cal, the display method proceeds to a step 41 of increasing the distance d between the virtual camera of the display device 1 and the point of interest P determined and at a step 42 of decreasing the angle 25 of the virtual view. In other words, the virtual view displayed on the screen of the electronic display device is one in a plane parallel to a substantially horizontal plane and the point of interest is remote from the virtual camera of the electronic display device. If the angle a is greater than the first threshold value S1 increased by the calibration value Cal, that is a> Si + Cal, the display method proceeds to a step 50 of comparing the angle a with a second threshold value S2, taking into account the Cal value of 3025645 8 calibration. By way of example, the second threshold value S2 can be set at 90 ° and the calibration value Cal can be set at 30 °. Thus, if the angle a is smaller than the second threshold value S2 minus the calibration value Cal, that is a <S2 - Cal, the display method proceeds to a step 61 of decreasing the distance d between the virtual camera of the display device 1 and the point of interest P determined in proportion to the value of the angle a and to a step 62 of increasing the angle of the virtual view. In other words, the virtual view displayed on the screen 6 of the electronic display device 1 is one in a plane inclined with respect to the horizontal plane and the point of interest P approaches the virtual camera of the device. 1. If the angle a is greater than or equal to the second threshold value S2 minus the calibration value, ie a> S2-Cal, the display method proceeds to a step 71 of decreasing the distance d between the virtual camera of the display device 1 and the point of interest P determined proportionally to the value of the angle a and to a step 72 of increasing the angle of the virtual view until reaching a three-dimensional view. In other words, the virtual view displayed on the screen 6 of the electronic display device 1 is a three-dimensional view and the point of interest P is at the level of the virtual camera of the electronic display device 1. In order to illustrate the operation of the display method, reference may be made to FIGS. 3 to 5.

In FIG. 3A is shown the electronic display device 1 of center of gravity G, a first axis a perpendicular to the display device 1 and passing through its center of gravity G and a second vertical axis A also passing through the center of gravity G. The angle a is the angle formed by the first straight line 30a with respect to the second line A. As shown in FIG. 3A, the angle a is 30 °. By way of example, if a first threshold value 51 of 0 ° and a calibration value Cal of 30 ° are taken, the angle a being equal to the threshold value 3025645 9 Si increased by the calibration value , a = Si + Cal, the virtual map view, shown in Figure 3B is in two dimensions, that is to say a plan view parallel to a horizontal plane. In general, when the display device 1 is positioned in a substantially horizontal plane with respect to the ground, the virtual map view is displayed in two dimensions. In other words, the angle between the virtual camera and the horizontal plane is equal to 0 °. Cal calibration value makes it possible to benefit from a two-dimensional display when the display device 1 is positioned in a more or less horizontal plane, that is to say included, for example, between 0 ° and 30 °. °. As shown in Figure 4A, the angle α is 45 °. By way of example, if we take a first threshold value S1 of 0 °, a second threshold value S2 of 90 ° and a calibration value Cal of 30 °, the angle a being greater than the first threshold value S1 increased by the calibration value and lower than the second threshold value S2 minus the calibration value, ie Si + Cal <a <S2-Cal, the virtual cartographic view, represented in FIG. 4B, is inclined by compared to the virtual view illustrated in Figure 3B. Similarly, the distance d between the virtual camera and the point of interest P is decreased with respect to the distance between the virtual camera and the point of interest P when the angle a is less than or equal to the first value of threshold If increased by calibration value Cal. In other words, the angle between the virtual camera and the horizontal plane 25 is proportional to the value of the angle α, here 45 °. As shown in Figure 5A, the angle α is 80 °. The angle a is therefore greater than the second threshold value S2 minus the calibration value Cal. The virtual map view, shown in FIG. 5B, is represented in three dimensions and the distance d 30 between the virtual camera and the point of interest P is decreased so as to be confused with the virtual camera. In general, when the display device 1 is positioned in a substantially vertical plane with respect to the ground, the virtual map view is displayed in three dimensions. In other words, the angle between the virtual camera and the horizontal plane is equal to 90 °. Cal calibration value makes it possible to benefit from a three-dimensional display when the display device 1 is positioned in a more or less vertical plane, that is to say included, for example, between 60 ° and 90 °. °. Note that one could compare the value of the angle with several threshold values Si, i being between 1 and n, in order to make the passage between the virtual views more fluid, that is to say the 10 change from cartographic view in two-dimensional mode to a three-dimensional mode and vice versa. As illustrated in FIG. 2, the display processing system 5 comprises a module 5a for comparing the angle α with the threshold values S i, i being between 1, a module 5b for adjusting the display. orientation of the virtual camera view as a function of the angle α and a control module 5c of the distance d between the point of interest P and the virtual camera. Thanks to the invention, a two-dimensional allocentric cartographic view is available when the nomadic electronic display device is positioned in a substantially horizontal plane with respect to the ground and a cartographic view which inclines gradually according to the angle between the nomadic electronic display device and the vertical plane to arrive at a three-dimensional egocentric map view when the angle between the nomadic electronic display device and the horizontal vertical plane is substantially equal to 90 ° . The display method according to the invention can, depending on the angular position of the electronic display device, that is to say the angle between the axis perpendicular to the electronic display device and the vertical axis 30 through its center of gravity, adjust the orientation of the view of the displayed virtual camera as well as the distance between the electronic display device and the point of interest.

3025645 11 Starting from a standard two-dimensional virtual map view, we can thus end up with a totally immersive virtual view that makes the virtual map view particularly close to the real map view. In order to make the virtual view even more real, it is possible to use the device 3 for geographical location or geolocation, and / or the device 4 for indicating the direction of the magnetic north. Note that it is also possible to use an offline map database that does not require these geolocation and / or magnetic north indication devices.

Claims (10)

REVENDICATIONS1. Method for displaying and adjusting the orientation of a virtual view for a nomadic electronic display device (1) comprising at least one screen (6) for displaying the virtual view and a device (2) for detecting the angular position (a) of the display device (1) with respect to a substantially vertical axis (A) relative to the ground passing through the center of gravity (G) of the display device (1), characterized in that that the orientation of the virtual view displayed on the screen (6) and the distance between the electronic display device (1) and a predetermined point of interest (P) is adjusted as a function of the angular position ( a) of the display device (1). 2. Display method according to claim 1, comprising a step (20) for measuring by the device (2) for detecting the angular position, the angle (a) formed between a straight line (a) perpendicular to the device. display (1) and passing through its center of gravity (G) and the line (A) and at least one step of comparing (30, 50) the angle (a) with at least one threshold value (Si ). 3. The display method according to claim 2, wherein a calibration value (Cal) of calibration of the threshold values (Si) is parameterized. 4. Display method according to claim 3, wherein when the angle (a) is less than or equal to a first threshold value (51) increased by the calibration value (Cal), the angle of the virtual view to a two-dimensional view and moving the display device (1) away from the point of interest (P), and wherein when the angle (a) is greater than the first threshold value (51) increased of the calibration value (Cal), a second step (50) for comparing the angle (a) with a second threshold value (S2) is carried out, taking into account the calibration value (Cal). 5. Display method according to claim 4, wherein when the angle (a) is less than the second threshold value (S2) minus the calibration value (Cal), the angle of the virtual view is oriented. proportionally to the angular position (a) of the display device (1) and the display device (1) is brought closer to the point of interest (P). The display method according to claim 4 or 5, wherein when the angle (a) is greater than or equal to the second threshold value (S2) minus the calibration value (Cal), the angle of the virtual view to a three-dimensional view and centering the display device (1) on the point of interest (P). The display method according to any one of claims 4 to 6, wherein the first threshold value (S1) is equal to 0 °, the second threshold value (S2) is equal to 90 °, and the calibration value (Cal) is between 0 ° and 30 °. 8. Display method according to any one of claims 1 to 7, wherein the device (2) for detecting the angular position is a gyro sensor or an accelerometer. 15 9. Display method according to any one of claims 1 to 8, wherein the electronic display device (1) comprises a device (4) for indicating the direction of magnetic north. 10. Nomadic electronic display device (1) comprising at least one screen (6) for displaying a virtual view and a device (2) for detecting the angular position (a) of the display device (1). ) with respect to a substantially vertical axis with respect to the ground passing through the center of gravity of the display device (1) and a display processing system (5) embodying the display method according to the any of the preceding claims.