This change will use the image engine to draw the backdrop of the compositor. With this patch the alpha blending will be done in Linear Scene Reference space and shows pure emissive colors.
See differential for an example image.
**Technical changes**
As only the backdrop drawing is done using the draw manager there are some technical changes.
1. The overlay buffer is partly drawn outside the draw manager. When drawing the backdrop image the overlay buffer needs to be masked to simulate premultiplied alpha under.
2. The backdrop of the node editor is done in region pixel space. A `DRWView` is constructed with this space.
3. UDIM textures uses world position to generate the UV coordinates. This has been implemented more strict by the `IMAGE_DRAW_FLAG_USE_WORLD_POS`. When the flag isn't used the local coordinates are used to generate the UV coordinates what is image space.
4. The draw manager now checks the actual `eSpaceType` of the space data to use different code paths. In the future the movie clip editor will be added.
NOTE: The preview images in nodes are drawn in display space and cannot show pure emissive colors. As preview images are used on more locations it is best to fix this in a separate patch.
Reviewed By: Clément Foucault
Differential Revision: https://developer.blender.org/D9451
This project moves the current UV/Image editor drawing to the draw manager.
Why would we do this:
**Performance**:
Current implementation would draw each texel per time. Multiple texels could be
drawn per pixel what would overwrite the previous result. You can notice this
when working with large textures. Repeat image drawing made this visible by
drawing for a small period of time and stop drawing the rest. Now the rendering
is fast and all repeated images are drawn.
**Alpha drawing**:
Current implementation would draw directly in display space. Giving incorrect
results when displaying alpha transparent images.
This addresses {T52680}, {T74709}, {T79518}
The image editor now can show emission only colors. See {D8234} for
examples.
**Current Limitations**
Using images that are larger than supported by your GPU are resized (eg larger
than 16000x16000 are resized to 8k). This leaves some blurring artifacts. It is
a low priority to add support back of displaying individual pixels of huge
images. There is a design task {T80113} with more detail.
**Implementation overview**
Introduced an Image Engine in the draw module. this engine is responsible for
drawing the texture in the main area of the UV/Image editor. The overlay engine
has a edit_uv overlay which is responsible to draw the UV's, shadows and
overlays specifically for the UV Image editor. The background + checker pattern
is drawn by the overlay_background.
The patch will allow us to share overlays between the 3d viewport and UV/Image
editor more easily. In most cases we just need to switch the `pos` with the `u`
attribute in the vertex shader.
The project can be activated in the user preferences as experimental features.
In a later commit this will be reversed.
Reviewed By: Clément Foucault
Differential Revision: https://developer.blender.org/D8234
This is the unification of all overlays into one overlay engine as described in T65347.
I went over all the code making it more future proof with less hacks and removing old / not relevent parts.
Goals / Acheivements:
- Remove internal shader usage (only drw shaders)
- Remove viewportSize and viewportSizeInv and put them in gloabl ubo
- Fixed some drawing issues: Missing probe option and Missing Alt+B clipping of some shader
- Remove old (legacy) shaders dependancy (not using view UBO).
- Less shader variation (less compilation time at first load and less patching needed for vulkan)
- removed some geom shaders when I could
- Remove static e_data (except shaders storage where it is OK)
- Clear the way to fix some anoying limitations (dithered transparency, background image compositing etc...)
- Wireframe drawing now uses the same batching capabilities as workbench & eevee (indirect drawing).
- Reduced complexity, removed ~3000 Lines of code in draw (also removed a lot of unused shader in GPU).
- Post AA to avoid complexity and cost of MSAA.
Remaining issues:
- ~~Armature edits, overlay toggles, (... others?) are not refreshing viewport after AA is complete~~
- FXAA is not the best for wires, maybe investigate SMAA
- Maybe do something more temporally stable for AA.
- ~~Paint overlays are not working with AA.~~
- ~~infront objects are difficult to select.~~
- ~~the infront wires sometimes goes through they solid counterpart (missing clear maybe?) (toggle overlays on-off when using infront+wireframe overlay in solid shading)~~
Note: I made some decision to change slightly the appearance of some objects to simplify their drawing. Namely the empty arrows end (which is now hollow/wire) and distance points of the cameras/spots being done by lines.
Reviewed By: jbakker
Differential Revision: https://developer.blender.org/D6296
