SG painting on image object

[ghost]

Feature description

The feature allows drawing on image objects in the shot-generator scene. It allows drawing on multiple images at the same time, by selecting the brush tab in image object it enables drawing mode in which you can't interact with objects (moving them and selecting them) but you can draw on images. Drawing on images updates image objects across the apps(shot-explorer and XR).
Changed image geometry to rounded plane geometry.

Solution description

To easily control all images and drawing on them their drawing material is stored in SceneManager. When image created it creates a specific drawing material that has a canvas, and it passes this object to SceneManager. SceneManager has all mouse events which is necessary for drawing, the drawing is only allowed when drawing mode is enabled. In order to change image texture( saving current drawing), each image uses a temp texture while the scene isn't saved. If the scene was saved image temp texture changes to original texture with new drawing in it, if the scene wasn't saved the temp texture file gets cleaned up.

Task

• Create drawing material logic which changes default image material and allows to draw on it
• Create 2 brushes( simple and eraser)
• Add brush tab and drawing mode
• Create temp image saving logic
• Update images across apps(XR and shot-explorer)
• Create pencil icon @setpixel

Future Plans

1. The simple brushes should be improved to draw smoother
2. Implement continuous drawing for an image( currently, if you move the mouse too fast it breaks a line)
3. Add the ability to draw on images to XR

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