Add polar.shader

data/examples/polar.shader

@@ -0,0 +1,66 @@
+#define PI 3.14159265359
+#define PI_2 6.2831
+#define mod(x,y) (x - y * floor(x / y))
+
+uniform float center_x<
+    string label = "Center x";
+    string widget_type = "slider";
+    float minimum = 0.0;
+    float maximum = 1.0;
+    float step = 0.001;
+> = 0.5;
+uniform float center_y<
+    string label = "Center y";
+    string widget_type = "slider";
+    float minimum = 0.0;
+    float maximum = 1.0;
+    float step = 0.001;
+> = 0.5;
+
+uniform float point_y<
+    string label = "Point y";
+    string widget_type = "slider";
+    float minimum = -1.0;
+    float maximum = 1.0;
+    float step = 0.001;
+> = 0.0;
+
+uniform bool flip;
+
+uniform float rotate<
+    string label = "Rotate";
+    string widget_type = "slider";
+    float minimum = 0.0;
+    float maximum = 1.0;
+    float step = 0.001;
+> = 0.0;
+
+uniform float repeat<
+    string label = "Repeat";
+    string widget_type = "slider";
+    float minimum = 0.0;
+    float maximum = 20.0;
+    float step = 0.001;
+> = 1.0;
+
+uniform float scale<
+    string label = "Scale";
+    string widget_type = "slider";
+    float minimum = 0.0;
+    float maximum = 2.0;
+    float step = 0.001;
+> = 0.5;
+
+float4 mainImage(VertData v_in) : TARGET
+{
+    float2 uv = v_in.uv;
+    uv.x -= center_x ;
+    uv.y -= center_y ;
+    uv.x = uv.x * ( uv_size.x / uv_size.y);
+    float pixel_angle = mod(atan2(uv.x,uv.y)/PI_2*repeat+0.5+rotate, 1.0);
+    float pixel_distance = length(uv)/ scale - point_y;
+    float2 uv2 = float2(pixel_angle , pixel_distance);
+    if(flip)
+        uv2.y = 1.0 - uv2.y;
+    return image.Sample(textureSampler,uv2);
+}