X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=builtin_data%2F_sky_backdrop.glsl;fp=builtin_data%2F_sky_backdrop.glsl;h=0aac6c8080553da91a246b18f7dd6d010be11e5a;hb=06d83c11e10208478487dea864ddd7822630c391;hp=0000000000000000000000000000000000000000;hpb=e98956208676c77e74462f17932ac530077a0540;p=libs%2Fgl.git

diff --git a/builtin_data/_sky_backdrop.glsl b/builtin_data/_sky_backdrop.glsl
new file mode 100644
index 00000000..0aac6c80
--- /dev/null
+++ b/builtin_data/_sky_backdrop.glsl
@@ -0,0 +1,22 @@
+import msp_interface;
+import _sky;
+
+uniform sampler2D distant;
+
+#pragma MSP stage(vertex)
+void main()
+{
+	gl_Position = vec4(vertex.xy, 1.0, 1.0);
+	mat4 inv_projection = inverse(projection_matrix);
+	out vec4 view_dir = inv_projection*vec4(vertex.xy, -1.0, 1.0);
+	view_dir /= view_dir.w;
+	view_dir = inverse(eye_world_matrix)*vec4(view_dir.xyz, 0.0);
+}
+
+#pragma MSP stage(fragment)
+void main()
+{
+	vec3 nview = normalize(view_dir.xyz);
+	float azimuth = atan(nview.y, nview.x);
+	frag_color = texture(distant, vec2(azimuth/(2*pi), nview.z*0.5+0.5))*light_color;
+}