relief map support, small refactoring, shadow bias now based on geometry normal

shaders/shadow.glsl

@@ -4,13 +4,16 @@ flat out uint object_flags;
 out float distance;
 out vec4 pos;
 
+const vec3 luma = vec3(0.299, 0.587, 0.114);
+
 void main(void) {
 	object_flags = qgl_ObjectFlags;
 	if (bitfieldExtract(object_flags, 2, 1) == 0)
 		return;
 	qgl_MaterialIndex = qgl_Material;
 	qgl_FragTexture = qgl_getFragTexture();
-	pos = qgl_ftransform();
+	float height = dot(qgl_materialTexture(QGL_MAP_RELIEF, qgl_FragTexture, vec4(0.)).rgb, luma);
+	pos = qgl_ViewProjMatrix * (qgl_ModelMatrix * (vec4(qgl_Vertex + qgl_Normal * height, 1.)));//qgl_ftransform();
 	gl_Position = pos;
 }