RadialBlur offset and angle interpretation changed

10 files changed, 17 insertions, 9 deletions

diff --git a/doc/src/images/RadialBlur_angle1.png b/doc/src/images/RadialBlur_angle1.png
index ac3d2aa..10eed9b 100644
--- a/doc/src/images/RadialBlur_angle1.png
+++ b/doc/src/images/RadialBlur_angle1.png
diff --git a/doc/src/images/RadialBlur_angle2.png b/doc/src/images/RadialBlur_angle2.png
index e340f90..0212f03 100644
--- a/doc/src/images/RadialBlur_angle2.png
+++ b/doc/src/images/RadialBlur_angle2.png
diff --git a/doc/src/images/RadialBlur_angle3.png b/doc/src/images/RadialBlur_angle3.png
index aedba92..3b26786 100644
--- a/doc/src/images/RadialBlur_angle3.png
+++ b/doc/src/images/RadialBlur_angle3.png
diff --git a/doc/src/images/RadialBlur_butterfly.png b/doc/src/images/RadialBlur_butterfly.png
index 46374a4..69314be 100755..100644
--- a/doc/src/images/RadialBlur_butterfly.png
+++ b/doc/src/images/RadialBlur_butterfly.png
diff --git a/doc/src/images/RadialBlur_horizontalOffset1.png b/doc/src/images/RadialBlur_horizontalOffset1.png
index 41df082..5f34885 100644
--- a/doc/src/images/RadialBlur_horizontalOffset1.png
+++ b/doc/src/images/RadialBlur_horizontalOffset1.png
diff --git a/doc/src/images/RadialBlur_horizontalOffset2.png b/doc/src/images/RadialBlur_horizontalOffset2.png
index 880f68c..771f727 100644
--- a/doc/src/images/RadialBlur_horizontalOffset2.png
+++ b/doc/src/images/RadialBlur_horizontalOffset2.png
diff --git a/doc/src/images/RadialBlur_horizontalOffset3.png b/doc/src/images/RadialBlur_horizontalOffset3.png
index 054a535..e1d6c37 100644
--- a/doc/src/images/RadialBlur_horizontalOffset3.png
+++ b/doc/src/images/RadialBlur_horizontalOffset3.png
diff --git a/doc/src/qtgraphicaleffects-radialblur.qdoc b/doc/src/qtgraphicaleffects-radialblur.qdoc
index 6fbb282..19aea5c 100644
--- a/doc/src/qtgraphicaleffects-radialblur.qdoc
+++ b/doc/src/qtgraphicaleffects-radialblur.qdoc
@@ -86,7 +86,7 @@
     If angle value is large, more samples are needed to keep the visual quality
     at high level.
 
-    Allowed values are between -360.0 and 360.0.
+    Allowed values are between 0.0 and 360.0.
     By default the property is set to \c 0.0.
 
     \table
@@ -167,9 +167,9 @@
     interpreted to be transparent, which is similar to OpenGL clamp-to-border
     extension. The blur is expanded slightly outside the effect item area.
 
-    If the property is set to \c false, the pixels outside the source are 
-    interpreted to contain the same color as the pixels at the edge of the item, 
-    which is similar to OpenGL clamp-to-edge behavior. The blur does not expand 
+    If the property is set to \c false, the pixels outside the source are
+    interpreted to contain the same color as the pixels at the edge of the item,
+    which is similar to OpenGL clamp-to-edge behavior. The blur does not expand
     outside the effect item area.
 
     By default, the property is set to \c false.
diff --git a/src/effects/RadialBlur.qml b/src/effects/RadialBlur.qml
index b44d134..0e63c7b 100644
--- a/src/effects/RadialBlur.qml
+++ b/src/effects/RadialBlur.qml
@@ -74,6 +74,8 @@ Item {
         property bool transparentBorder: rootItem.transparentBorder && rootItem.samples > 1
         property int samples: rootItem.samples
         property real weight: 1.0 / Math.max(1.0, rootItem.samples)
+        property real angleSin: Math.sin(rootItem.angle/2 * Math.PI/180)
+        property real angleCos: Math.cos(rootItem.angle/2 * Math.PI/180)
         property real angleSinStep: Math.sin(-rootItem.angle * Math.PI/180 / Math.max(1.0, rootItem.samples - 1))
         property real angleCosStep: Math.cos(-rootItem.angle * Math.PI/180 / Math.max(1.0, rootItem.samples - 1))
         property variant expandPixels: transparentBorder ? Qt.size(0.5 * parent.height, 0.5 * parent.width) : Qt.size(0,0)
@@ -91,6 +93,8 @@ Item {
             varying highp vec2 qt_TexCoord0;
             uniform highp float qt_Opacity;
             uniform sampler2D source;
+            uniform highp float angleSin;
+            uniform highp float angleCos;
             uniform highp float angleSinStep;
             uniform highp float angleCosStep;
             uniform highp float weight;
@@ -102,14 +106,18 @@ Item {
 
             void main(void) {
                 highp mat2 m;
-                m[0] = vec2(angleCosStep, -angleSinStep);
-                m[1] = vec2(angleSinStep, angleCosStep);
                 gl_FragColor = vec4(0.0);
                 mediump vec2 texCoord = qt_TexCoord0;
 
                 PLACEHOLDER_EXPAND_STEPS
 
-                highp vec2 dir = vec2(texCoord.s * w - w * 0.5, texCoord.t * h - h * 0.5);
+                highp vec2 dir = vec2(texCoord.s * w - w * center.x, texCoord.t * h - h * center.y);
+                m[0] = vec2(angleCos, -angleSin);
+                m[1] = vec2(angleSin, angleCos);
+                dir *= m;
+
+                m[0] = vec2(angleCosStep, -angleSinStep);
+                m[1] = vec2(angleSinStep, angleCosStep);
 
                 PLACEHOLDER_UNROLLED_LOOP
 
diff --git a/tests/manual/testbed/TestRadialBlur.qml b/tests/manual/testbed/TestRadialBlur.qml
index 037ce6f..217329c 100644
--- a/tests/manual/testbed/TestRadialBlur.qml
+++ b/tests/manual/testbed/TestRadialBlur.qml
@@ -72,8 +72,8 @@ TestCaseTemplate {
             caption: "general"
             Slider {
                 id: lengthSlider
-                minimum: -180.0
-                maximum: 180.0
+                minimum: 0.0
+                maximum: 360.0
                 value: 15.0
                 caption: "angle"
             }