Optimized Directional, Radial and ZoomBlur effects.

Weight multiplication was inside the unrolled loop,
moved that to the end of the shader. Additionally
expand calculation is now done with vectors.

Change-Id: Idc27e9dfd2d6911d3e65d093fb043a07cb912a1c
Reviewed-by: Kim Gronholm <kim.1.gronholm@nokia.com>

3 files changed, 10 insertions, 14 deletions

diff --git a/src/effects/DirectionalBlur.qml b/src/effects/DirectionalBlur.qml
index 47cc2ac..63e1c0a 100644
--- a/src/effects/DirectionalBlur.qml
+++ b/src/effects/DirectionalBlur.qml
@@ -103,7 +103,7 @@ Item {
 
                 PLACEHOLDER_UNROLLED_LOOP
 
-                gl_FragColor *= qt_Opacity;
+                gl_FragColor *= weight * qt_Opacity;
            }
         "
 
@@ -112,8 +112,7 @@ Item {
             var expandSteps = ""
 
             if (transparentBorder) {
-                expandSteps += "texCoord.s = (texCoord.s - expand.x) / (1.0 - 2.0 * expand.x);"
-                expandSteps += "texCoord.t = (texCoord.t - expand.y) / (1.0 - 2.0 * expand.y);"
+                expandSteps += "texCoord = (texCoord - expand) / (1.0 - 2.0 * expand);"
             }
 
             var unrolledLoop = "gl_FragColor += texture2D(source, texCoord);\n"
@@ -121,7 +120,7 @@ Item {
             if (rootItem.samples > 1) {
                 unrolledLoop = ""
                 for (var i = 0; i < rootItem.samples; i++)
-                    unrolledLoop += "gl_FragColor += texture2D(source, texCoord) * weight; texCoord += shift;\n"
+                    unrolledLoop += "gl_FragColor += texture2D(source, texCoord); texCoord += shift;\n"
             }
 
             shader = shader.replace("PLACEHOLDER_EXPAND_STEPS", expandSteps)
diff --git a/src/effects/RadialBlur.qml b/src/effects/RadialBlur.qml
index aff3c3d..830ebec 100644
--- a/src/effects/RadialBlur.qml
+++ b/src/effects/RadialBlur.qml
@@ -121,7 +121,7 @@ Item {
 
                 PLACEHOLDER_UNROLLED_LOOP
 
-                gl_FragColor *= qt_Opacity;
+                gl_FragColor *= weight * qt_Opacity;
             }
         "
 
@@ -130,8 +130,7 @@ Item {
             var expandSteps = ""
 
             if (transparentBorder) {
-                expandSteps += "texCoord.s = (texCoord.s - expand.x) / (1.0 - 2.0 * expand.x);"
-                expandSteps += "texCoord.t = (texCoord.t - expand.y) / (1.0 - 2.0 * expand.y);"
+                expandSteps += "texCoord = (texCoord - expand) / (1.0 - 2.0 * expand);"
             }
 
             var unrolledLoop = "gl_FragColor += texture2D(source, texCoord);\n"
@@ -139,7 +138,7 @@ Item {
             if (rootItem.samples > 1) {
                  unrolledLoop = ""
                  for (var i = 0; i < rootItem.samples; i++)
-                     unrolledLoop += "texCoord = vec2(center.x + dir.x * delta.x, center.y + dir.y * delta.y); gl_FragColor += texture2D(source, texCoord) * weight; dir *= m;\n"
+                     unrolledLoop += "gl_FragColor += texture2D(source, center + dir * delta); dir *= m;\n"
             }
 
             shader = shader.replace("PLACEHOLDER_EXPAND_STEPS", expandSteps)
diff --git a/src/effects/ZoomBlur.qml b/src/effects/ZoomBlur.qml
index 83c6173..c784014 100644
--- a/src/effects/ZoomBlur.qml
+++ b/src/effects/ZoomBlur.qml
@@ -108,7 +108,7 @@ Item {
 
                 PLACEHOLDER_UNROLLED_LOOP
 
-                gl_FragColor *= qt_Opacity;
+                gl_FragColor *= weight * qt_Opacity;
             }
         "
 
@@ -117,10 +117,8 @@ Item {
             var expandSteps = ""
 
             if (transparentBorder) {
-                 expandSteps += "centerCoord.s = (centerCoord.s - expand.x) / (1.0 - 2.0 * expand.x);"
-                 expandSteps += "centerCoord.t = (centerCoord.t - expand.y) / (1.0 - 2.0 * expand.y);"
-                 expandSteps += "texCoord.s = (texCoord.s - expand.x) / (1.0 - 2.0 * expand.x);"
-                 expandSteps += "texCoord.t = (texCoord.t - expand.y) / (1.0 - 2.0 * expand.y);"
+                expandSteps += "centerCoord = (centerCoord - expand) / (1.0 - 2.0 * expand);"
+                expandSteps += "texCoord = (texCoord - expand) / (1.0 - 2.0 * expand);"
              }
 
              var unrolledLoop = "gl_FragColor += texture2D(source, texCoord);\n"
@@ -128,7 +126,7 @@ Item {
              if (rootItem.samples > 1) {
                  unrolledLoop = ""
                  for (var i = 0; i < rootItem.samples; i++)
-                      unrolledLoop += "gl_FragColor += texture2D(source, texCoord) * weight; texCoord += shift;\n"
+                      unrolledLoop += "gl_FragColor += texture2D(source, texCoord); texCoord += shift;\n"
              }
 
              shader = shader.replace("PLACEHOLDER_EXPAND_STEPS", expandSteps)