In cases when specular highlights are not desired, results in 30%
speedup (on Intel) and ~25% speedup on AMD, compared to setting the
specular color to transparent black.
Testing was easy thanks to already having a ground truth image for this
case.
After several failed attempts to make UBO performance not suck on Intel
Mesa and Windows drivers, I ended up hiding the dynamic aspect under a
flag. That way it's still possible to get the proper perf in UBO
workflows that don't do light culling, and for workflows where light
culling matters the 2x slowdown might be still better than looping
through several extra lights that don't contribute anything.
This is always true in the single-draw case, since setDrawOffset()
asserts on this. In the multi-draw case this optimization doesn't make
sense, because it doesn't make sense to create a multidraw shader with
just one draw.
On an Intel 630 GPU this resulted in single-draw single-material Phong
to go from 550 ms to 440, which is roughly a 20% improvement. For the
simpler shaders the difference is even higher. The multidraw numbers
stayed the same as before, obviously.
This is a -- long overdue -- breaking change to the rendering output of
this shader, finally adding support for lights that get darker over
distance. The attenuation equation is basically what's documented in
LightData, and the distinction between directional and point lights is
made using a newly added the fourth component of position (which means
the old three-component setters are all deprecated). This allows the
shader code to be practically branchless, which I find to be nice.
This breaks basically all rendering output so all existing Phong and
MeshTools::compile() test outputs had to be regenerated.
It's needed to support the new material attributes supported by glTF.
The test output is slightly different as the normal coming from
the texture wasn't normalized before.
Except MeshVisualizer and VertexColor, which don't have any texturing,
so there it's not needed. In most cases the tests are reusing existing
ground truth files and only modifying transformations / flipping images.
As usual, the old APIs are still present, but marked as deprecated.
Existing code is not updated yet to ensure I didn't break anything with
this.
This way it's much more intuitive and makes the code shorter and nicer
in many cases. Shaders are now also able to hide irrelevant
draw/dispatch APIs to avoid accidents.
Should make new things more discoverable, avoid confusion when a
documented API isn't there and reduce the need for maintaining multiple
separate versions of the docs.
Note -- since there are no visual tests for Phong yet, this is done in
the least intrusive manner to avoid breaking current functionality. It's
likely very underperforming due to the matric calculation per fragment,
it'll get optimized once I have proper tests.