Remove qtgraphicaleffects sources and add note about its state in Qt 6HEADdev

Add a README.md mentioning the documentation on where the ported
effects can be found, as well as how to check out the Qt5 branch.

Pick-to: 6.2
Fixes: QTBUG-95757
Change-Id: Ib47c7e73f8622c8e287df0f74c6f16a5113b357e
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

1 files changed, 0 insertions, 30 deletions

diff --git a/src/effects/shaders_ng/rectangularglow.frag b/src/effects/shaders_ng/rectangularglow.frag
deleted file mode 100644
index cf20b93..0000000
--- a/src/effects/shaders_ng/rectangularglow.frag
+++ /dev/null
@@ -1,30 +0,0 @@
-#version 440
-
-layout(location = 0) in vec2 qt_TexCoord0;
-layout(location = 0) out vec4 fragColor;
-
-layout(std140, binding = 0) uniform buf {
-    // qt_Matrix and qt_Opacity must always be both present
-    // if the built-in vertex shader is used.
-    mat4 qt_Matrix;
-    float qt_Opacity;
-    vec4 color;
-    float relativeSizeX;
-    float relativeSizeY;
-    float spread;
-};
-
-float linearstep(float e0, float e1, float x)
-{
-    return clamp((x - e0) / (e1 - e0), 0.0, 1.0);
-}
-
-void main()
-{
-    float alpha =
-        smoothstep(0.0, relativeSizeX, 0.5 - abs(0.5 - qt_TexCoord0.x)) *
-        smoothstep(0.0, relativeSizeY, 0.5 - abs(0.5 - qt_TexCoord0.y));
-
-    float spreadMultiplier = linearstep(spread, 1.0 - spread, alpha);
-    fragColor = color * qt_Opacity * spreadMultiplier * spreadMultiplier;
-}