1 files changed, 31 insertions, 0 deletions
diff --git a/src/quick/scenegraph/shaders_ng/distancefieldoutlinetext_a_fwidth.frag b/src/quick/scenegraph/shaders_ng/distancefieldoutlinetext_a_fwidth.frag
new file mode 100644
index 0000000000..478b217054
--- /dev/null
+++ b/src/quick/scenegraph/shaders_ng/distancefieldoutlinetext_a_fwidth.frag
@@ -0,0 +1,31 @@
+#version 440
+
+layout(location = 0) in vec2 sampleCoord;
+layout(location = 0) out vec4 fragColor;
+
+layout(binding = 1) uniform sampler2D _qt_texture;
+
+layout(std140, binding = 0) uniform buf {
+    mat4 matrix;
+    vec2 textureScale;
+    vec4 color;
+    float alphaMin;
+    float alphaMax;
+    // up to this point it must match distancefieldtext
+    vec4 styleColor;
+    float outlineAlphaMax0;
+    float outlineAlphaMax1;
+} ubuf;
+
+void main()
+{
+    float distance = texture(_qt_texture, sampleCoord).a;
+    float f = fwidth(distance);
+
+    // The outlineLimit is based on font size, but scales with the transform, so
+    // we can calculate it from the outline span.
+    float outlineLimit = (ubuf.outlineAlphaMax1 - ubuf.outlineAlphaMax0) / 2.0 + ubuf.outlineAlphaMax0;
+
+    fragColor = mix(ubuf.styleColor, ubuf.color, smoothstep(max(0.0, 0.5 - f), min(1.0, 0.5 + f), distance))
+            * smoothstep(max(0.0, outlineLimit - f), min(outlineLimit + f, 0.5 - f), distance);
+}