New custom material example

Fixes: QTBUG-78577
Change-Id: I280ffeda4bba1a9c170feb1ffa4b6c95eb0e6d28
Reviewed-by: Laszlo Agocs <[email protected]>

1 files changed, 48 insertions, 0 deletions

diff --git a/examples/quick/scenegraph/custommaterial/shaders/mandelbrot.frag b/examples/quick/scenegraph/custommaterial/shaders/mandelbrot.frag
new file mode 100644
index 0000000000..0e5f63e7a8
--- /dev/null
+++ b/examples/quick/scenegraph/custommaterial/shaders/mandelbrot.frag
@@ -0,0 +1,48 @@
+//! [1]
+#version 440
+
+layout(location = 0) in vec2 vTexCoord;
+
+layout(location = 0) out vec4 fragColor;
+
+//! [2]
+// uniform block: 84 bytes
+layout(std140, binding = 0) uniform buf {
+    mat4 qt_Matrix; // offset 0
+    float qt_Opacity; // offset 64
+    float zoom; // offset 68
+    vec2 center; // offset 72
+    int limit; // offset 80
+} ubuf;
+//! [2]
+
+void main()
+{
+    vec4 color1 = vec4(1.0, 0.85, 0.55, 1);
+    vec4 color2 = vec4(0.226, 0.0, 0.615, 1);
+
+    float aspect_ratio = -ubuf.qt_Matrix[0][0]/ubuf.qt_Matrix[1][1];
+    vec2 z, c;
+
+    c.x = (vTexCoord.x - 0.5) / ubuf.zoom + ubuf.center.x;
+    c.y = aspect_ratio * (vTexCoord.y - 0.5) / ubuf.zoom + ubuf.center.y;
+
+    int i;
+    z = c;
+    for (i = 0; i < ubuf.limit; i++) {
+        float x = (z.x * z.x - z.y * z.y) + c.x;
+        float y = (z.y * z.x + z.x * z.y) + c.y;
+
+        if ((x * x + y * y) > 4.0) break;
+        z.x = x;
+        z.y = y;
+    }
+
+    if (i == ubuf.limit) {
+        fragColor = vec4(0.0, 0.0, 0.0, 1.0);
+    } else {
+        float f = (i * 1.0) / ubuf.limit;
+        fragColor = mix(color1, color2, sqrt(f));
+    }
+}
+//! [1]