Modified: trunk/Source/WebCore/ChangeLog (120544 => 120545)
--- trunk/Source/WebCore/ChangeLog 2012-06-17 03:55:36 UTC (rev 120544)
+++ trunk/Source/WebCore/ChangeLog 2012-06-17 04:42:18 UTC (rev 120545)
@@ -1,3 +1,27 @@
+2012-06-16 Huang Dongsung <[email protected]>
+
+ [Texmap] Share gaussian formula between shaders in TextureMapperShaderManager.
+ https://bugs.webkit.org/show_bug.cgi?id=89277
+
+ This patch makes blur and drop shadow shader share gaussian formula.
+
+ On the other hand, blur and drop shadow filter computed a gaussian weight in
+ pixel shader. However, a gaussian kernal has always same values, so this patch
+ computes the gaussian kernel only one time using CPU.
+ It is more accurate and faster.
+
+ Reviewed by Noam Rosenthal.
+
+ Covered by existing tests, particularly css3/filters/.
+
+ * platform/graphics/texmap/TextureMapperShaderManager.cpp:
+ (WebCore):
+ (WebCore::StandardFilterProgram::StandardFilterProgram):
+ (WebCore::gauss):
+ (WebCore::gaussianKernel):
+ (WebCore::StandardFilterProgram::prepare):
+ * platform/graphics/texmap/TextureMapperShaderManager.h:
+
2012-06-16 Robert Kroeger <[email protected]>
[chromium] Make the deviceScaleFactor dynamically adjustable.
Modified: trunk/Source/WebCore/platform/graphics/texmap/TextureMapperShaderManager.cpp (120544 => 120545)
--- trunk/Source/WebCore/platform/graphics/texmap/TextureMapperShaderManager.cpp 2012-06-17 03:55:36 UTC (rev 120544)
+++ trunk/Source/WebCore/platform/graphics/texmap/TextureMapperShaderManager.cpp 2012-06-17 04:42:18 UTC (rev 120545)
@@ -38,10 +38,12 @@
"precision mediump float; \n"
#endif
-#define VERTEX_SHADER(src...) OES2_PRECISION_DEFINITIONS#src
+#define STRINGIFY_VAL(src...) #src
+#define VERTEX_SHADER(src...) OES2_PRECISION_DEFINITIONS\
+ STRINGIFY_VAL(src)
#define FRAGMENT_SHADER(src...) OES2_PRECISION_DEFINITIONS\
OES2_FRAGMENT_SHADER_DEFAULT_PRECISION\
- #src
+ STRINGIFY_VAL(src)
static const char* fragmentShaderSourceOpacityAndMask =
FRAGMENT_SHADER(
@@ -352,6 +354,11 @@
}
#if ENABLE(CSS_FILTERS)
+
+// Create a normal distribution of 21 values between -2 and 2.
+#define GAUSSIAN_KERNEL_HALF_WIDTH 11
+#define GAUSSIAN_KERNEL_STEP 0.2
+
StandardFilterProgram::~StandardFilterProgram()
{
glDetachShader(m_id, m_vertexShader);
@@ -475,16 +482,8 @@
varying highp vec2 v_texCoord;
uniform lowp vec2 u_blurRadius;
uniform sampler2D u_texture;
- const float pi = 3.14159;
- const float e = 2.71828;
+ uniform float u_gaussianKernel[GAUSSIAN_KERNEL_HALF_WIDTH];
- // FIXME: share gaussian formula between shaders.
- lowp float gaussian(lowp float value)
- {
- // Normal distribution formula, when the mean is 0 and the standard deviation is 1.
- return pow(e, -pow(value, 2.) / 2.) / (sqrt(2. * pi));
- }
-
lowp vec4 sampleColor(float radius)
{
vec2 coord = v_texCoord + radius * u_blurRadius;
@@ -493,16 +492,13 @@
vec4 blur()
{
- // Create a normal distribution of 20 values between 0. and 2.
- vec4 total = vec4(0., 0., 0., 0.);
- float totalWeight = 0.;
- for (float i = -2.; i <= 2.; i += .2) {
- float weight = gaussian(i);
- total += sampleColor(i) * weight;
- totalWeight += weight;
+ vec4 total = sampleColor(0) * u_gaussianKernel[0];
+ for (int i = 1; i < GAUSSIAN_KERNEL_HALF_WIDTH; i++) {
+ total += sampleColor(float(i) * GAUSSIAN_KERNEL_STEP) * u_gaussianKernel[i];
+ total += sampleColor(float(-1 * i) * GAUSSIAN_KERNEL_STEP) * u_gaussianKernel[i];
}
- return total / totalWeight;
+ return total;
}
void main(void)
@@ -520,16 +516,8 @@
uniform lowp float u_shadowBlurRadius;
uniform lowp vec2 u_shadowOffset;
uniform sampler2D u_texture;
- const float pi = 3.14159;
- const float e = 2.71828;
+ uniform float u_gaussianKernel[GAUSSIAN_KERNEL_HALF_WIDTH];
- // FIXME: share gaussian formula between shaders.
- lowp float gaussian(lowp float value)
- {
- // Normal distribution formula, when the mean is 0 and the standard deviation is 1.
- return pow(e, -pow(value, 2.) / 2.) / (sqrt(2. * pi));
- }
-
lowp float sampleAlpha(float radius)
{
vec2 coord = v_texCoord - u_shadowOffset + vec2(radius * u_shadowBlurRadius, 0.);
@@ -538,16 +526,13 @@
lowp float shadowBlurHorizontal()
{
- // Create a normal distribution of 20 values between -2 and 2.
- float total = 0.;
- float totalWeight = 0.;
- for (float i = -2.; i <= 2.; i += .2) {
- float weight = gaussian(i);
- total += sampleAlpha(i) * weight;
- totalWeight += weight;
+ float total = sampleAlpha(0) * u_gaussianKernel[0];
+ for (int i = 1; i < GAUSSIAN_KERNEL_HALF_WIDTH; i++) {
+ total += sampleAlpha(float(i) * GAUSSIAN_KERNEL_STEP) * u_gaussianKernel[i];
+ total += sampleAlpha(float(-1 * i) * GAUSSIAN_KERNEL_STEP) * u_gaussianKernel[i];
}
- return total / totalWeight;
+ return total;
}
void main(void)
@@ -565,17 +550,8 @@
uniform lowp vec4 u_shadowColor;
uniform sampler2D u_texture;
uniform sampler2D u_contentTexture;
+ uniform float u_gaussianKernel[GAUSSIAN_KERNEL_HALF_WIDTH];
- // FIXME: share gaussian formula between shaders.
- const float pi = 3.14159;
- const float e = 2.71828;
-
- lowp float gaussian(float value)
- {
- // Normal distribution formula, when the mean is 0 and the standard deviation is 1.
- return pow(e, -pow(value, 2.) / 2.) / (sqrt(2. * pi));
- }
-
lowp float sampleAlpha(float r)
{
vec2 coord = v_texCoord + vec2(0., r * u_shadowBlurRadius);
@@ -584,16 +560,13 @@
lowp float shadowBlurVertical()
{
- // Create a normal distribution of 20 values between -2 and 2.
- float total = 0.;
- float totalWeight = 0.;
- for (float i = -2.; i <= 2.; i += .2) {
- float weight = gaussian(i);
- total += sampleAlpha(i) * weight;
- totalWeight += weight;
+ float total = sampleAlpha(0) * u_gaussianKernel[0];
+ for (int i = 1; i < GAUSSIAN_KERNEL_HALF_WIDTH; i++) {
+ total += sampleAlpha(float(i) * GAUSSIAN_KERNEL_STEP) * u_gaussianKernel[i];
+ total += sampleAlpha(float(-1 * i) * GAUSSIAN_KERNEL_STEP) * u_gaussianKernel[i];
}
- return total / totalWeight;
+ return total;
}
lowp vec4 sourceOver(lowp vec4 source, lowp vec4 destination)
@@ -650,9 +623,11 @@
break;
case FilterOperation::BLUR:
m_uniformLocations.blur.radius = glGetUniformLocation(programID, "u_blurRadius");
+ m_uniformLocations.blur.gaussianKernel = glGetUniformLocation(programID, "u_gaussianKernel");
break;
case FilterOperation::DROP_SHADOW:
m_uniformLocations.shadow.blurRadius = glGetUniformLocation(programID, "u_shadowBlurRadius");
+ m_uniformLocations.shadow.gaussianKernel = glGetUniformLocation(programID, "u_gaussianKernel");
if (!pass)
m_uniformLocations.shadow.offset = glGetUniformLocation(programID, "u_shadowOffset");
else {
@@ -678,6 +653,35 @@
return program;
}
+static inline float gauss(float x)
+{
+ return exp(-(x * x) / 2.);
+}
+
+static float* gaussianKernel()
+{
+ static bool prepared = false;
+ static float kernel[GAUSSIAN_KERNEL_HALF_WIDTH] = {0, };
+
+ if (prepared)
+ return kernel;
+
+ kernel[0] = gauss(0);
+ float sum = kernel[0];
+ for (unsigned i = 1; i < GAUSSIAN_KERNEL_HALF_WIDTH; ++i) {
+ kernel[i] = gauss(i * GAUSSIAN_KERNEL_STEP);
+ sum += 2 * kernel[i];
+ }
+
+ // Normalize the kernel
+ float scale = 1 / sum;
+ for (unsigned i = 0; i < GAUSSIAN_KERNEL_HALF_WIDTH; ++i)
+ kernel[i] *= scale;
+
+ prepared = true;
+ return kernel;
+}
+
void StandardFilterProgram::prepare(const FilterOperation& operation, unsigned pass, const IntSize& size, GLuint contentTexture)
{
glUseProgram(m_id);
@@ -705,6 +709,7 @@
radius.setWidth(floatValueForLength(blur.stdDeviation(), size.width()) / size.width());
glUniform2f(m_uniformLocations.blur.radius, radius.width(), radius.height());
+ glUniform1fv(m_uniformLocations.blur.gaussianKernel, GAUSSIAN_KERNEL_HALF_WIDTH, gaussianKernel());
break;
}
case FilterOperation::DROP_SHADOW: {
@@ -714,10 +719,12 @@
// First pass: vertical alpha blur.
glUniform2f(m_uniformLocations.shadow.offset, float(shadow.location().x()) / float(size.width()), float(shadow.location().y()) / float(size.height()));
glUniform1f(m_uniformLocations.shadow.blurRadius, shadow.stdDeviation() / float(size.width()));
+ glUniform1fv(m_uniformLocations.shadow.gaussianKernel, GAUSSIAN_KERNEL_HALF_WIDTH, gaussianKernel());
break;
case 1:
// Second pass: we need the shadow color and the content texture for compositing.
glUniform1f(m_uniformLocations.shadow.blurRadius, shadow.stdDeviation() / float(size.height()));
+ glUniform1fv(m_uniformLocations.shadow.gaussianKernel, GAUSSIAN_KERNEL_HALF_WIDTH, gaussianKernel());
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, contentTexture);
glUniform1i(m_uniformLocations.shadow.contentTexture, 1);
