Image engine uses 4 gpu textures that are as large as the area being
drawn. The amount of needed GPU memory can be reduced by dividing the
region in smaller parts. Reducing the GPU memory also reduces the stalls
when updating the textures, improving the performance as well.
This optimization works, but is disabled for now due to some rounding
errors that drawn lines on the screen where the screen is divided.
It used to be a number of fixed full screen images where the
responsibility was at image engine. Now moved the responsibility to the
drawing mode to make sure we can allocate non-full region-size textures
in a future refactoring.
`get_gpu_textures` was created when the image engine didn't support
texture streaming and used the gpu textures that were stored in the
image buffer itself.
Float images loaded in Blender are converted to scene linear and don't
require additional conversion. Image engine can reuse the rect_float of
those images. An assert statement is added tp make this more clear and
to test on missing code paths or future developments.
Texture usage flags can now be provided during texture creation specifying
the ways in which a texture can be used. This allows the GPU backends to
perform contextual optimizations which were not previously possible. This
includes enablement of hardware lossless compression which can result in
a 15%+ performance uplift for bandwidth-limited scenes on hardware such
as Apple-Silicon using Metal.
GPU_TEXTURE_USAGE_GENERAL can be used by default if usage is not known
ahead of time. Patch will also be relevant for the Vulkan backend.
Authored by Apple: Michael Parkin-White
Ref T96261
Reviewed By: fclem
Differential Revision: https://developer.blender.org/D15967
Image engine is used to draw the image inside the image editor, uv editor and node editor. The
performance during scrolling wasn't smooth when using larger textures on a dedicated GPU. Main
reason was the data transfers that happens when panning the image.
The original idea of the image engine was to have 4 textures that are as large as the editor.
Those textures would be used to simulate a larger canvas where if the texture is out of the
visible area the texture would be reused to contain the data of a new visible area. This would
reduce the data transfers to only on certain x/y coordinates. Between those coordinates no
data transfers would be needed.
This patch implements the mechanism described above. During development other areas to
improve have been detected (incorrect color management for float textures, using different
image formats to reduce data transfer bandwidths, using different render techniques for
images upto 8k). More improvements will follow.
When image data exceeds half float ranges values are set to +/-
infinity that could lead to artifacts later on in the pipeline.
Color management for example.
This patch adds a utility function `IMB_gpu_clamp_half_float`
that clamps full float values to fit within the range of
half floats.
This fixes T98575 and T101601.
This is the conventional way of dealing with unused arguments in C++,
since it works on all compilers.
Regex find and replace: `UNUSED\((\w+)\)` -> `/*$1*/`
When resizing a viewport all engine instance data was cleared.
This wasn't the intended design and lead to performance regressions
in the image engine.
This patch makes sure that the instance data isn't cleared when
the viewport size changes. When using instance data, draw engines
are responsible to update the textures accordingly.
This could also reduce flickering/stalling when resizing the viewport
in eevee-next.
Fixes T95428.
Reviewed By: fclem
Maniphest Tasks: T95428
Differential Revision: https://developer.blender.org/D14874
- Missing star prefix.
- Unnecessary indentation.
- Blank line after dot-points
(otherwise doxygen merges with the previous dot-point).
- Use back-slash for doxygen commands.
- Correct spelling.
ImageTileWrapper is a wrapper around ImageTile to centralize tile calculations when
using CPP. Currentry used by the image engine and will be used for the 3d
texturing brush project.
For render image buffers to be acquired, a lock must be provided. Also
fixed wrong usage of release, it must always be called regardless if the
returned image buffer is NULL.
This is only part of the experimental "Full Frame" mode (disabled
by default). See T88150.
Currently the viewer node uses buffer paddings to display image offset
in the backdrop as a temporal solution implemented for {D12466}.
This solution is inefficient memory and performance-wise. Another
issue is that the paddings are part the image when saved.
This patch instead sets the offset in the Viewer node image
as variables and makes the backdrop take it into account
when drawing the image or any related gizmo.
Reviewed By: jbakker
Differential Revision: https://developer.blender.org/D12750
The image engine is depth aware when using tile drawing the depth is
only updated for the central image what lead to showing the background
on top of other areas.
Also makes sure that switching the tile drawing would lead to an update
of the texture slots.
Internally the update tiles are 256x256. Due to some miscalculations
tiles were not generated correctly if the dimension of the image wasn't
a multifold of 256.
Previously we used to cache a float image representation of the image in
rect_float. This adds some incorrect behavior as many areas only expect
one of these buffers to be used.
This patch stores float buffers inside the image engine. This is done per
instance. In the future we should consider making a global cache.
Althought the float buffers are only used as cache, current code paths
don't look at the flags to identify which kind of image it is. Actual
fix would be to check flags, but that wouldn't be something to add one
week before release.
This commit fixes it by removing the buffers after use in the image
engine.
Previous implementation had a copy of the image user, which doesn't
contain all the data to identify changes. This patch introduces a new
struct to store the data and can be extended with other data as well
(color spaces, alpha settings).
