Support Musgrave texture for Cycles GLSL viewport

Only for non-OSX viewport!

1 files changed, 221 insertions, 6 deletions

diff --git a/source/blender/gpu/shaders/gpu_shader_material.glsl b/source/blender/gpu/shaders/gpu_shader_material.glsl
index e97dddfd00f..dcb888b1a9b 100644
--- a/source/blender/gpu/shaders/gpu_shader_material.glsl
+++ b/source/blender/gpu/shaders/gpu_shader_material.glsl
@@ -2875,12 +2875,6 @@ void node_tex_magic(vec3 co, float scale, float distortion, float depth, out vec
 	fac = (color.x + color.y + color.z) / 3.0;
 }
 
-void node_tex_musgrave(vec3 co, float scale, float detail, float dimension, float lacunarity, float offset, float gain, out vec4 color, out float fac)
-{
-	color = vec4(1.0);
-	fac = 1.0;
-}
-
 #ifdef BIT_OPERATIONS
 float noise_fade(float t)
 {
@@ -2934,6 +2928,11 @@ float noise(vec3 p)
 	return 0.5 * noise_perlin(p.x, p.y, p.z) + 0.5;
 }
 
+float snoise(vec3 p)
+{
+	return noise_perlin(p.x, p.y, p.z);
+}
+
 float noise_turbulence(vec3 p, float octaves, int hard)
 {
 	float fscale = 1.0;
@@ -2993,6 +2992,222 @@ void node_tex_noise(vec3 co, float scale, float detail, float distortion, out ve
 #endif  // BIT_OPERATIONS
 }
 
+
+#ifdef BIT_OPERATIONS
+
+/* Musgrave fBm
+ *
+ * H: fractal increment parameter
+ * lacunarity: gap between successive frequencies
+ * octaves: number of frequencies in the fBm
+ *
+ * from "Texturing and Modelling: A procedural approach"
+ */
+
+float noise_musgrave_fBm(vec3 p, float H, float lacunarity, float octaves)
+{
+	float rmd;
+	float value = 0.0;
+	float pwr = 1.0;
+	float pwHL = pow(lacunarity, -H);
+	int i;
+
+	for(i = 0; i < int(octaves); i++) {
+		value += snoise(p) * pwr;
+		pwr *= pwHL;
+		p *= lacunarity;
+	}
+
+	rmd = octaves - floor(octaves);
+	if(rmd != 0.0)
+		value += rmd * snoise(p) * pwr;
+
+	return value;
+}
+
+/* Musgrave Multifractal
+ *
+ * H: highest fractal dimension
+ * lacunarity: gap between successive frequencies
+ * octaves: number of frequencies in the fBm
+ */
+
+float noise_musgrave_multi_fractal(vec3 p, float H, float lacunarity, float octaves)
+{
+	float rmd;
+	float value = 1.0;
+	float pwr = 1.0;
+	float pwHL = pow(lacunarity, -H);
+	int i;
+
+	for(i = 0; i < int(octaves); i++) {
+		value *= (pwr * snoise(p) + 1.0);
+		pwr *= pwHL;
+		p *= lacunarity;
+	}
+
+	rmd = octaves - floor(octaves);
+	if(rmd != 0.0)
+		value *= (rmd * pwr * snoise(p) + 1.0); /* correct? */
+
+	return value;
+}
+
+/* Musgrave Heterogeneous Terrain
+ *
+ * H: fractal dimension of the roughest area
+ * lacunarity: gap between successive frequencies
+ * octaves: number of frequencies in the fBm
+ * offset: raises the terrain from `sea level'
+ */
+
+float noise_musgrave_hetero_terrain(vec3 p, float H, float lacunarity, float octaves, float offset)
+{
+	float value, increment, rmd;
+	float pwHL = pow(lacunarity, -H);
+	float pwr = pwHL;
+	int i;
+
+	/* first unscaled octave of function; later octaves are scaled */
+	value = offset + snoise(p);
+	p *= lacunarity;
+
+	for(i = 1; i < int(octaves); i++) {
+		increment = (snoise(p) + offset) * pwr * value;
+		value += increment;
+		pwr *= pwHL;
+		p *= lacunarity;
+	}
+
+	rmd = octaves - floor(octaves);
+	if(rmd != 0.0) {
+		increment = (snoise(p) + offset) * pwr * value;
+		value += rmd * increment;
+	}
+
+	return value;
+}
+
+/* Hybrid Additive/Multiplicative Multifractal Terrain
+ *
+ * H: fractal dimension of the roughest area
+ * lacunarity: gap between successive frequencies
+ * octaves: number of frequencies in the fBm
+ * offset: raises the terrain from `sea level'
+ */
+
+float noise_musgrave_hybrid_multi_fractal(vec3 p, float H, float lacunarity, float octaves, float offset, float gain)
+{
+	float result, signal, weight, rmd;
+	float pwHL = pow(lacunarity, -H);
+	float pwr = pwHL;
+	int i;
+
+	result = snoise(p) + offset;
+	weight = gain * result;
+	p *= lacunarity;
+
+	for(i = 1; (weight > 0.001f) && (i < int(octaves)); i++) {
+		if(weight > 1.0)
+			weight = 1.0;
+
+		signal = (snoise(p) + offset) * pwr;
+		pwr *= pwHL;
+		result += weight * signal;
+		weight *= gain * signal;
+		p *= lacunarity;
+	}
+
+	rmd = octaves - floor(octaves);
+	if(rmd != 0.0)
+		result += rmd * ((snoise(p) + offset) * pwr);
+
+	return result;
+}
+
+/* Ridged Multifractal Terrain
+ *
+ * H: fractal dimension of the roughest area
+ * lacunarity: gap between successive frequencies
+ * octaves: number of frequencies in the fBm
+ * offset: raises the terrain from `sea level'
+ */
+
+float noise_musgrave_ridged_multi_fractal(vec3 p, float H, float lacunarity, float octaves, float offset, float gain)
+{
+	float result, signal, weight;
+	float pwHL = pow(lacunarity, -H);
+	float pwr = pwHL;
+	int i;
+
+	signal = offset - abs(snoise(p));
+	signal *= signal;
+	result = signal;
+	weight = 1.0;
+
+	for(i = 1; i < int(octaves); i++) {
+		p *= lacunarity;
+		weight = clamp(signal * gain, 0.0, 1.0);
+		signal = offset - abs(snoise(p));
+		signal *= signal;
+		signal *= weight;
+		result += signal * pwr;
+		pwr *= pwHL;
+	}
+
+	return result;
+}
+
+float svm_musgrave(int type,
+                   float dimension,
+                   float lacunarity,
+                   float octaves,
+                   float offset,
+                   float intensity,
+                   float gain,
+                   vec3 p)
+{
+	if (type == 0 /*NODE_MUSGRAVE_MULTIFRACTAL*/)
+		return intensity*noise_musgrave_multi_fractal(p, dimension, lacunarity, octaves);
+	else if (type == 1 /*NODE_MUSGRAVE_FBM*/)
+		return intensity*noise_musgrave_fBm(p, dimension, lacunarity, octaves);
+	else if (type == 2 /*NODE_MUSGRAVE_HYBRID_MULTIFRACTAL*/)
+		return intensity*noise_musgrave_hybrid_multi_fractal(p, dimension, lacunarity, octaves, offset, gain);
+	else if (type == 3 /*NODE_MUSGRAVE_RIDGED_MULTIFRACTAL*/)
+		return intensity*noise_musgrave_ridged_multi_fractal(p, dimension, lacunarity, octaves, offset, gain);
+	else if (type == 4 /*NODE_MUSGRAVE_HETERO_TERRAIN*/)
+		return intensity*noise_musgrave_hetero_terrain(p, dimension, lacunarity, octaves, offset);
+	return 0.0;
+}
+#endif  // #ifdef BIT_OPERATIONS
+
+void node_tex_musgrave(vec3 co,
+                       float scale,
+                       float detail,
+                       float dimension,
+                       float lacunarity,
+                       float offset,
+                       float gain,
+                       float type,
+                       out vec4 color,
+                       out float fac)
+{
+#ifdef BIT_OPERATIONS
+	fac = svm_musgrave(int(type),
+	                   dimension,
+	                   lacunarity,
+	                   detail,
+	                   offset,
+	                   1.0,
+	                   gain,
+	                   co*scale);
+#else
+	fac = 1.0;
+#endif
+
+	color = vec4(fac, fac, fac, 1.0);
+}
+
 void node_tex_sky(vec3 co, out vec4 color)
 {
 	color = vec4(1.0);