Image Engine redesign. #92525

New Issue

Jeroen Bakker · 2021-10-27T10:17:05+02:00

Jeroen Bakker commented

2021-10-27 10:17:05 +02:00

The GPU Viewport module have discussed some limitations of the image engine (the code that draws the image editor, node editor backdrop,..)

Images are scaled down when they don't fit in a gpu texture. GPUs have different max resolutions.
GPU textures are all cached inside the Image struct. This leads to complicated code as there are many variations that needs to be tracked.

Approach

Every visible image/node editor would keep track of the images they need.
The image editor would keep track of a small number (4-8) of screen sized textures.
When panning the textures are drawn with an translation. When an image isn't visible (moved to a side of the screen) the image would be reused as it is needed at the other side of the screen.
The GPU textures should be reused when zooming inside a certain range. When outside the range the GPU textures would be recreated. There might be a slight delay when this happens.

Repeated Images

Images can be set repeated. In this solution the image will be drawn repeated inside the screen sized textures.

Tiled Images

Tiled images are rendered in screen space inside the screen sized textures.

Image Channel

When switching the image channel can update the screen sized textures (Eg showing the depth) As switching the image channel is done via a user interaction the update/upload of the data might not be noticable by the user.

Stereo drawing

An idea is to have stereo drawing becoming a responsibility of draw engines. In case of the image editor we creating the left/right image at the same time as they use the same panning, zoom level and image channel.

Partial update

When painting textures are partially updated. This mechanism needs an overhaul as there are now multiple areas that needs to implement partial updating. Storing the area for partial updates cannot be the Image anymore. Perhaps an idea to look at the message bus and if we can use it.
#92613 (GPUTexture partial update) describes a proposal for partial updating.

#80113 (Support Huge Image Sizes in image/uv editor)

The GPU Viewport module have discussed some limitations of the image engine (the code that draws the image editor, node editor backdrop,..) * Images are scaled down when they don't fit in a gpu texture. GPUs have different max resolutions. * GPU textures are all cached inside the Image struct. This leads to complicated code as there are many variations that needs to be tracked. ## Approach * Every visible image/node editor would keep track of the images they need. * The image editor would keep track of a small number (4-8) of screen sized textures. * When panning the textures are drawn with an translation. When an image isn't visible (moved to a side of the screen) the image would be reused as it is needed at the other side of the screen. * The GPU textures should be reused when zooming inside a certain range. When outside the range the GPU textures would be recreated. There might be a slight delay when this happens. ### Repeated Images Images can be set repeated. In this solution the image will be drawn repeated inside the screen sized textures. ### Tiled Images Tiled images are rendered in screen space inside the screen sized textures. ### Image Channel When switching the image channel can update the screen sized textures (Eg showing the depth) As switching the image channel is done via a user interaction the update/upload of the data might not be noticable by the user. ### Stereo drawing An idea is to have stereo drawing becoming a responsibility of draw engines. In case of the image editor we creating the left/right image at the same time as they use the same panning, zoom level and image channel. ### Partial update When painting textures are partially updated. This mechanism needs an overhaul as there are now multiple areas that needs to implement partial updating. Storing the area for partial updates cannot be the Image anymore. Perhaps an idea to look at the message bus and if we can use it. #92613 (GPUTexture partial update) describes a proposal for partial updating. ## Related tasks * #80113 (Support Huge Image Sizes in image/uv editor)

Jeroen Bakker self-assigned this 2021-10-27 10:17:05 +02:00

Jeroen Bakker commented

2021-10-27 10:17:05 +02:00

Changed status from 'Needs Triage' to: 'Confirmed'