X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=builtin_data%2F_envmap_irradiance.glsl;fp=builtin_data%2F_envmap_irradiance.glsl;h=83b62c858099b83c98e1277755b318d24309c4a4;hb=6b9338845dfee441cd18ad6c633e4feef8ad14e1;hp=0000000000000000000000000000000000000000;hpb=87b74b1263710b0acb9e0b72283e972fd54ee91b;p=libs%2Fgl.git

diff --git a/builtin_data/_envmap_irradiance.glsl b/builtin_data/_envmap_irradiance.glsl
new file mode 100644
index 00000000..83b62c85
--- /dev/null
+++ b/builtin_data/_envmap_irradiance.glsl
@@ -0,0 +1,21 @@
+import cubemap_effect;
+import _pbr_prefilter;
+
+#pragma MSP stage(fragment)
+layout(location=0) out vec3 frag_color;
+void main()
+{
+	vec3 normal = normalize(texcoord);
+	vec3 tangent = normalize(abs(normal.x)>abs(normal.y) ? vec3(-normal.z, 0.0, normal.x) : vec3(0.0, -normal.z, normal.y));
+	mat3 orientation = mat3(tangent, cross(normal, tangent), normal);
+
+	vec3 sum = vec3(0.0);
+	for(int i=0; i<n_samples; ++i)
+	{
+		vec2 uv = hammersley(i, n_samples);
+		vec3 dir = orientation*uv_to_hemisphere(uv.x, sqrt(1.0-uv.y));
+		sum += textureLod(environment_map, dir, 0).rgb;
+	}
+
+	frag_color = sum/n_samples;
+}