[occt.git] / src / Shaders / PBRFresnel.glsl

//! Functions to calculate fresnel coefficient and approximate zero fresnel value.
vec3 occPBRFresnel (in vec3  theBaseColor,
                    in float theMetallic,
                    in float theIOR)
{
  theIOR = (1.0 - theIOR) / (1.0 + theIOR);
  theIOR *= theIOR;
  vec3 f0 = vec3(theIOR);
  f0 = mix (f0, theBaseColor.rgb, theMetallic);
  return f0;
}

vec3 occPBRFresnel (in vec3  theBaseColor,
                    in float theMetallic,
                    in float theIOR,
                    in float theCosVH)
{
  vec3 f0 = occPBRFresnel (theBaseColor, theMetallic, theIOR);
  theCosVH = 1.0 - theCosVH;
  theCosVH *= theCosVH;
  theCosVH *= theCosVH * theCosVH * theCosVH * theCosVH;
  return f0 + (vec3 (1.0) - f0) * theCosVH;
}

vec3 occPBRFresnel (in vec3  theBaseColor,
                    in float theMetallic,
                    in float theRoughness,
                    in float theIOR,
                    in float theCosV)
{
  vec3 f0 = occPBRFresnel (theBaseColor, theMetallic, theIOR);
  theCosV = 1.0 - theCosV;
  theCosV *= theCosV;
  theCosV *= theCosV * theCosV * theCosV * theCosV;
  return f0 + (max(vec3(1.0 - theRoughness), f0) - f0) * theCosV;
}
Commit	Line	Data
67312b79	1	//! Functions to calculate fresnel coefficient and approximate zero fresnel value.
	2	vec3 occPBRFresnel (in vec3 theBaseColor,
	3	in float theMetallic,
	4	in float theIOR)
	5	{
	6	theIOR = (1.0 - theIOR) / (1.0 + theIOR);
	7	theIOR *= theIOR;
	8	vec3 f0 = vec3(theIOR);
	9	f0 = mix (f0, theBaseColor.rgb, theMetallic);
	10	return f0;
	11	}
	12
	13	vec3 occPBRFresnel (in vec3 theBaseColor,
	14	in float theMetallic,
	15	in float theIOR,
	16	in float theCosVH)
	17	{
	18	vec3 f0 = occPBRFresnel (theBaseColor, theMetallic, theIOR);
	19	theCosVH = 1.0 - theCosVH;
	20	theCosVH *= theCosVH;
	21	theCosVH = theCosVH theCosVH * theCosVH * theCosVH;
	22	return f0 + (vec3 (1.0) - f0) * theCosVH;
	23	}
	24
	25	vec3 occPBRFresnel (in vec3 theBaseColor,
	26	in float theMetallic,
	27	in float theRoughness,
	28	in float theIOR,
	29	in float theCosV)
	30	{
	31	vec3 f0 = occPBRFresnel (theBaseColor, theMetallic, theIOR);
	32	theCosV = 1.0 - theCosV;
	33	theCosV *= theCosV;
	34	theCosV = theCosV theCosV * theCosV * theCosV;
	35	return f0 + (max(vec3(1.0 - theRoughness), f0) - f0) * theCosV;
	36	}