Implement fixes to the distance field renderer

- Change modelView matrix to mvp for sharper texts
- Support global opacity from parents
- Allow changing alpha from the text color picker
- Change shadow color to be the same as the text color

Task-number: QT3DS-3343
Task-number: QT3DS-3363
Change-Id: I37178abe6c9239619a3f9de440d2b9245a138a82
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@qt.io>
Reviewed-by: Tomi Korpipää <tomi.korpipaa@qt.io>

6 files changed, 6 insertions, 10 deletions

diff --git a/src/Runtime/res/effectlib/distancefieldtext.vert b/src/Runtime/res/effectlib/distancefieldtext.vert
index a3feb378..01024c6b 100644
--- a/src/Runtime/res/effectlib/distancefieldtext.vert
+++ b/src/Runtime/res/effectlib/distancefieldtext.vert
@@ -1,5 +1,4 @@
 uniform highp mat4 mvp;
-uniform highp mat4 modelView;
 uniform highp float fontScale;
 uniform int textureWidth;
 uniform int textureHeight;
@@ -59,7 +58,7 @@ highp float determinant(highp mat4 m)
 
 void main()
 {
-    highp float scale = fontScale * sqrt(abs(determinant(modelView)));
+    highp float scale = fontScale * sqrt(abs(determinant(mvp)));
     alphas = alphaRange(scale);
     sampleCoord = tCoord * vec2(1.0 / highp float(textureWidth), 1.0 / highp float(textureHeight));
     gl_Position = mvp * vec4(vCoord, 1.0);
diff --git a/src/Runtime/res/effectlib/distancefieldtext_core.vert b/src/Runtime/res/effectlib/distancefieldtext_core.vert
index 1ced295c..ce6a165c 100644
--- a/src/Runtime/res/effectlib/distancefieldtext_core.vert
+++ b/src/Runtime/res/effectlib/distancefieldtext_core.vert
@@ -6,7 +6,6 @@ out vec2 sampleCoord;
 out vec2 alphas;
 
 uniform mat4 mvp;
-uniform mat4 modelView;
 uniform int textureWidth;
 uniform int textureHeight;
 uniform float fontScale;
@@ -37,7 +36,7 @@ vec2 alphaRange(float scale)
 
 void main()
 {
-     float scale = fontScale * sqrt(abs(determinant(modelView)));
+     float scale = fontScale * sqrt(abs(determinant(mvp)));
      alphas = alphaRange(scale);
      sampleCoord = tCoord * vec2(1.0 / float(textureWidth), 1.0 / float(textureHeight));
      gl_Position = mvp * vec4(vCoord, 1.0);
diff --git a/src/Runtime/res/effectlib/distancefieldtext_dropshadow.frag b/src/Runtime/res/effectlib/distancefieldtext_dropshadow.frag
index da51c5c2..94b277cd 100644
--- a/src/Runtime/res/effectlib/distancefieldtext_dropshadow.frag
+++ b/src/Runtime/res/effectlib/distancefieldtext_dropshadow.frag
@@ -15,7 +15,7 @@ void main()
                                                    clamp(shadowSampleCoord,
                                                          normalizedTextureBounds.xy,
                                                          normalizedTextureBounds.zw)).a);
-    highp vec4 shadowPixel = shadowColor * shadowAlpha;
+    highp vec4 shadowPixel = color * shadowColor * shadowAlpha;
 
     highp float textAlpha = smoothstep(alphas.x,
                                        alphas.y,
diff --git a/src/Runtime/res/effectlib/distancefieldtext_dropshadow.vert b/src/Runtime/res/effectlib/distancefieldtext_dropshadow.vert
index f645eb8c..f633aaa5 100644
--- a/src/Runtime/res/effectlib/distancefieldtext_dropshadow.vert
+++ b/src/Runtime/res/effectlib/distancefieldtext_dropshadow.vert
@@ -1,5 +1,4 @@
 uniform highp mat4 mvp;
-uniform highp mat4 modelView;
 uniform highp float fontScale;
 uniform int textureWidth;
 uniform int textureHeight;
@@ -63,7 +62,7 @@ highp float determinant(highp mat4 m)
 
 void main()
 {
-    highp float scale = fontScale * sqrt(abs(determinant(modelView)));
+    highp float scale = fontScale * sqrt(abs(determinant(mvp)));
     alphas = alphaRange(scale);
 
     highp vec2 textureSizeMultiplier = vec2(1.0 / highp float(textureWidth),
diff --git a/src/Runtime/res/effectlib/distancefieldtext_dropshadow_core.frag b/src/Runtime/res/effectlib/distancefieldtext_dropshadow_core.frag
index 304b1874..4e46bd5f 100644
--- a/src/Runtime/res/effectlib/distancefieldtext_dropshadow_core.frag
+++ b/src/Runtime/res/effectlib/distancefieldtext_dropshadow_core.frag
@@ -18,7 +18,7 @@ void main()
                                            clamp(shadowSampleCoord,
                                                  normalizedTextureBounds.xy,
                                                  normalizedTextureBounds.zw)).r);
-    vec4 shadowPixel = shadowColor * shadowAlpha;
+    vec4 shadowPixel = color * shadowColor * shadowAlpha;
 
     float textAlpha = smoothstep(alphas.x,
                                  alphas.y,
diff --git a/src/Runtime/res/effectlib/distancefieldtext_dropshadow_core.vert b/src/Runtime/res/effectlib/distancefieldtext_dropshadow_core.vert
index 3b1ba712..9be245b8 100644
--- a/src/Runtime/res/effectlib/distancefieldtext_dropshadow_core.vert
+++ b/src/Runtime/res/effectlib/distancefieldtext_dropshadow_core.vert
@@ -9,7 +9,6 @@ out vec2 alphas;
 out vec4 normalizedTextureBounds;
 
 uniform mat4 mvp;
-uniform mat4 modelView;
 uniform int textureWidth;
 uniform int textureHeight;
 uniform float fontScale;
@@ -41,7 +40,7 @@ vec2 alphaRange(float scale)
 
 void main()
 {
-     float scale = fontScale * sqrt(abs(determinant(modelView)));
+     float scale = fontScale * sqrt(abs(determinant(mvp)));
      alphas = alphaRange(scale);
 
      vec2 textureSizeMultiplier = vec2(1.0 / float(textureWidth), 1.0 / float(textureHeight));