strepsirrhini/office-gobmx
9
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

slideshow: Add an ugly workaround for Intel’s matrix multiplication

Browse source 
When more than three multiplications are chained, Intel’s Windows
driver returns a mat4 containing only zeroes, likely due to a
misbehaving optimisation.  This patch prevents it from doing any
optimisation by doing each multiplication in its own uniform block.

Change-Id: I0b435d3a5444afd47f78c379f0d2e442d2c2cfc0
Reviewed-on: https://gerrit.libreoffice.org/22470
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>
This commit is contained in:
Emmanuel Gil Peyrot 2016-02-24 20:21:12 +00:00 committed by Tomaž Vajngerl
parent 0640430902
commit db9fe1ea4a
2 changed files with 42 additions and 14 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

41
slideshow/opengl/honeycombVertexShader.glsl
View file

@ -25,10 +25,21 @@ uniform float shadow;
uniform mat4 orthoProjectionMatrix;
uniform mat4 orthoViewMatrix;
// Workaround for Intel's Windows driver, to prevent optimisation breakage.
uniform float zero;
out mat4 projectionMatrix;
out mat4 modelViewMatrix;
out mat4 shadowMatrix;
mat4 identityMatrix(void)
{
return mat4(1.0, 0.0, 0.0, 0.0,
0.0, 1.0, 0.0, 0.0,
0.0, 0.0, 1.0, 0.0,
0.0, 0.0, 0.0, 1.0);
}
mat4 translationMatrix(vec3 axis)
{
return mat4(1.0, 0.0, 0.0, 0.0,
@ -61,25 +72,35 @@ mat4 rotationMatrix(vec3 axis, float angle)
void main( void )
{
mat4 nmodelViewMatrix = u_modelViewMatrix * u_operationsTransformMatrix * u_sceneTransformMatrix * u_primitiveTransformMatrix;
mat4 transformMatrix;
mat4 transformMatrix = identityMatrix();
// TODO: use the aspect ratio of the slide instead.
mat4 slideScaleMatrix = scaleMatrix(vec3(0.75, 1, 1));
mat4 invertSlideScaleMatrix = scaleMatrix(1.0 / vec3(0.75, 1, 1));
// These ugly zero comparisons are a workaround for Intel's Windows driver optimisation bug.
if (selectedTexture > 0.5) {
// Leaving texture
transformMatrix = translationMatrix(vec3(0, 0, 6 * time))
* scaleMatrix(vec3(1 + pow(2 * time, 2.1), 1 + pow(2 * time, 2.1), 0))
* slideScaleMatrix
* rotationMatrix(vec3(0.0, 0.0, 1.0), -pow(time, 3) * M_PI)
* invertSlideScaleMatrix;
if (zero < 1.0)
transformMatrix = invertSlideScaleMatrix * transformMatrix;
if (zero < 2.0)
transformMatrix = rotationMatrix(vec3(0.0, 0.0, 1.0), -pow(time, 3) * M_PI) * transformMatrix;
if (zero < 3.0)
transformMatrix = slideScaleMatrix * transformMatrix;
if (zero < 4.0)
transformMatrix = scaleMatrix(vec3(1 + pow(2 * time, 2.1), 1 + pow(2 * time, 2.1), 0)) * transformMatrix;
if (zero < 5.0)
transformMatrix = translationMatrix(vec3(0, 0, 6 * time)) * transformMatrix;
} else {
// Entering texture
transformMatrix = translationMatrix(vec3(0, 0, 28 * (sqrt(time) - 1)))
* slideScaleMatrix
* rotationMatrix(vec3(0.0, 0.0, 1.0), pow(0.8 * (time - 1.0), 2.0) * M_PI)
* invertSlideScaleMatrix;
if (zero < 1.0)
transformMatrix = invertSlideScaleMatrix * transformMatrix;
if (zero < 2.0)
transformMatrix = rotationMatrix(vec3(0.0, 0.0, 1.0), pow(0.8 * (time - 1.0), 2.0) * M_PI) * transformMatrix;
if (zero < 3.0)
transformMatrix = slideScaleMatrix * transformMatrix;
if (zero < 4.0)
transformMatrix = translationMatrix(vec3(0, 0, 28 * (sqrt(time) - 1))) * transformMatrix;
}
if (shadow < 0.5) {

15
slideshow/opengl/vortexVertexShader.glsl
View file

@ -26,6 +26,9 @@ uniform ivec2 numTiles;
uniform sampler2D permTexture;
uniform float slide;
// Workaround for Intel's Windows driver, to prevent optimisation breakage.
uniform float zero;
out vec2 g_texturePosition;
out vec3 g_normal;
out mat4 modelViewMatrix;
@ -130,10 +133,14 @@ void main( void )
vec3 translationVector = vec3(rotationFuzz, 0.0, 0.0);
// Compute the actual rotation matrix.
transform = translationMatrix(translationVector)
* rotationMatrix(vec3(0.0, 1.0, 0.0), clamp(rotation, -1.0, 1.0) * M_PI)
* translationMatrix(-translationVector)
* transform;
// Intel's Windows driver gives a wrong matrix when all operations are done at once.
if (zero < 1.0)
transform = translationMatrix(translationVector) * transform;
if (zero < 2.0)
transform = rotationMatrix(vec3(0.0, 1.0, 0.0), clamp(rotation, -1.0, 1.0) * M_PI) * transform;
if (zero < 3.0)
transform = translationMatrix(-translationVector) * transform;
}
modelViewMatrix = u_modelViewMatrix * u_operationsTransformMatrix * u_sceneTransformMatrix * u_primitiveTransformMatrix;