Adds GrEffect::willUseInputColor() which indicates whether or not the
input color affects the output of the effect. This is needed for
certain Xfermodes, such as kSrc_Mode. For these modes the color filter
will not use the input color.
An effect with GrEffect::willUseInputColor() true will cause all color
or coverage effects before it to be discarded, as their computations
cannot affect the output. In these cases program is marked as having
white input color.
This fixes an assert when Skia is compiled in a mode that prefers
using uniforms instead of attributes for constants. (Flags
GR_GL_USE_NV_PATH_RENDERING or GR_GL_NO_CONSTANT_ATTRIBUTES). Using
attributes hides the problem where the fragment shader does not need
input color for color filters that ignore DST part of the filter. The
assert would be hit when uniform manager tries to bind an uniform which
has been optimized away by the shader compiler.
Adds specific GrGLSLExpr4 and GrGLSLExpr1 classes. This way the GLSL
expressions like "(v - src.a)" can remain somewhat readable in form of
"(v - src.a())". The GrGLSLExpr<typename> template implements the
generic functionality, GrGLSLExprX is the specialization that exposes
the type-safe interface to this functionality.
Also adds operators so that GLSL binary operators of the form
"(float * vecX)" can be expressed in C++. Before only the equivalent
"(vecX * float)" was possible. This reverts the common blending
calculations to more conventional order, such as "(1-a) * c" instead of
"c * (1-a)".
Changes GrGLSLExpr1::OnesStr from 1 to 1.0 in order to preserve the
color filter blending formula string the same (with the exception of
variable name change).
Shaders change in case of input color being needed:
- vec4 filteredColor;
- filteredColor = (((1.0 - uFilterColor.a) * output_Stage0) + uFilterColor);
- fsColorOut = filteredColor;
+ vec4 output_Stage1;
+ { // Stage 1: ModeColorFilterEffect
+ output_Stage1 = (((1.0 - uFilterColor_Stage1.a) * output_Stage0) + uFilterColor_Stage1);
+ }
+ fsColorOut = output_Stage1;
Shaders change in case of input color being not needed:
-uniform vec4 uFilterColor;
-in vec4 vColor;
+uniform vec4 uFilterColor_Stage0;
out vec4 fsColorOut;
void main() {
- vec4 filteredColor;
- filteredColor = uFilterColor;
- fsColorOut = filteredColor;
+ vec4 output_Stage0;
+ { // Stage 0: ModeColorFilterEffect
+ output_Stage0 = uFilterColor_Stage0;
+ }
+ fsColorOut = output_Stage0;
}
R=bsalomon@google.com, robertphillips@google.com, jvanverth@google.com
Author: kkinnunen@nvidia.com
Review URL: https://codereview.chromium.org/25023003
git-svn-id: http://skia.googlecode.com/svn/trunk@11912 2bbb7eff-a529-9590-31e7-b0007b416f81
Renames ShaderType in GrGLShaderBuilder to ShaderVisibility. It is now
used solely as a bitfield. Methods that previously accepted a single
ShaderType value are split into separate calls:
- getShader -> vsGetShader, gsGetShader, fsGetShader
- emiitFunction -> fsEmitFunction
- appendTextureLookup -> fsAppendTextureLookup
No change in functionality. This is a refactoring to allow us to
separate the vertex/geometry and fragment parts of GrGLShaderBuilder.
R=bsalomon@google.com
Author: cdalton@nvidia.com
Review URL: https://chromiumcodereview.appspot.com/23826002
git-svn-id: http://skia.googlecode.com/svn/trunk@11044 2bbb7eff-a529-9590-31e7-b0007b416f81
Enabling Perlin Noise on Android
I enabled the Perlin Noise shader on Android after doing some minor modifications to the shader, specifically for Android (and #ifdefed for Android, to make sure none of this affects other platforms).
For Tegra devices (Nexus 7, Xoom), a precision issue related to the color values read from textures caused the noise to read the wrong indices and produce bad noise. I fixed this by adding a founding of the values read by simply doing the equivalent of "colorValue = floor(colorValue * 255.0) / 255.0" to make sure we retrieve the colors that were written in the texture originally.
For non-Tegra devices (Nexus 10), dealing with values in the order of 4096.0 was problematic without using the "highp" precision setting. To solve this, a few variables were given the high precision setting.
Since both fixes don't seem to do considerable harm to the platforms that are not being targetted, I left both fixes on all android devices for now.
I also reduced the Perlin noise gm so that it takes less time to test it on the Xoom (Original time was about 20 seconds, this shold take less than 10, hopefully)
BUG=
R=senorblanco@google.com, bsalomon@google.com, sugoi@google.com, senorblanco@chromium.org
Author: sugoi@chromium.org
Review URL: https://chromiumcodereview.appspot.com/16818013
git-svn-id: http://skia.googlecode.com/svn/trunk@9637 2bbb7eff-a529-9590-31e7-b0007b416f81
I just cleaned up and re-ordered some instructions to reduce the number of registers used under the register limit. Instead of looping over channels, the function now only loops over octaves and computes all 4 channels separately within each octave loop. I made a noise function to make it simpler to make the changes and I fixed the code's alignment so that it's more readable.
R=bsalomon@google.com, senorblanco@chromium.org
Review URL: https://codereview.chromium.org/15753005
git-svn-id: http://skia.googlecode.com/svn/trunk@9486 2bbb7eff-a529-9590-31e7-b0007b416f81
1 ) Added GPU simplex noise as a comparison to GPU Perlin noise. It can be enabled simply by using a #define (SK_USE_SIMPLEX_NOISE)
2 ) Enabled GPU Perlin noise tests
3 ) Added a small benchmark for noise
4 ) Disabled GPU Perlin noise on Android based on benchmarks
Review URL: https://codereview.chromium.org/14087002
git-svn-id: http://skia.googlecode.com/svn/trunk@8719 2bbb7eff-a529-9590-31e7-b0007b416f81
