git subrepo clone (merge) https://github.com/HarbourMasters/otrgui.git OTRGui

subrepo:
  subdir:   "OTRGui"
  merged:   "a6066a251"
upstream:
  origin:   "https://github.com/HarbourMasters/otrgui.git"
  branch:   "master"
  commit:   "a6066a251"
git-subrepo:
  version:  "0.4.1"
  origin:   "???"
  commit:   "???"

OTRGui/libs/raylib/examples/models/resources/shaders/glsl330/cubemap.fs

@@ -0,0 +1,30 @@
+#version 330
+
+// Input vertex attributes (from vertex shader)
+in vec3 fragPosition;
+
+// Input uniform values
+uniform sampler2D equirectangularMap;
+
+// Output fragment color
+out vec4 finalColor;
+
+vec2 SampleSphericalMap(vec3 v)
+{
+    vec2 uv = vec2(atan(v.z, v.x), asin(v.y));
+    uv *= vec2(0.1591, 0.3183);
+    uv += 0.5;
+    return uv;
+}
+
+void main()
+{
+    // Normalize local position
+    vec2 uv = SampleSphericalMap(normalize(fragPosition));
+
+    // Fetch color from texture map
+    vec3 color = texture(equirectangularMap, uv).rgb;
+
+    // Calculate final fragment color
+    finalColor = vec4(color, 1.0);
+}