[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [56621] trunk/blender: Cycles bump node: change the Strength value to work better, previously it would

[Brecht Van Lommel]

Revision: 56621
          http://projects.blender.org/scm/viewvc.php?view=rev&root=bf-blender&revision=56621
Author:   blendix
Date:     2013-05-09 14:05:37 +0000 (Thu, 09 May 2013)
Log Message:
-----------
Cycles bump node: change the Strength value to work better, previously it would
give results that were either too weak or too strong, this makes it give more
predictable results. The downside is that it breaks backwards compatibility but
the previous behavior was almost broken.

Modified Paths:
--------------
    trunk/blender/intern/cycles/kernel/shaders/node_bump.osl
    trunk/blender/intern/cycles/kernel/svm/svm_displace.h
    trunk/blender/source/blender/nodes/shader/nodes/node_shader_bump.c

Modified: trunk/blender/intern/cycles/kernel/shaders/node_bump.osl
===================================================================
--- trunk/blender/intern/cycles/kernel/shaders/node_bump.osl	2013-05-09 14:01:42 UTC (rev 56620)
+++ trunk/blender/intern/cycles/kernel/shaders/node_bump.osl	2013-05-09 14:05:37 UTC (rev 56621)
@@ -40,10 +40,12 @@
 	float det = dot(dPdx, Rx);
 	vector surfgrad = (SampleX - SampleCenter) * Rx + (SampleY - SampleCenter) * Ry;
 
-	surfgrad *= Strength;
 	float absdet = fabs(det);
+
+	float strength = clamp(Strength, 0.0, 1.0);
 	
 	/* compute and output perturbed normal */
 	NormalOut = normalize(absdet * NormalIn - sign(det) * surfgrad);
+	NormalOut = normalize(strength*NormalOut + (1.0 - strength)*NormalIn);
 }
 

Modified: trunk/blender/intern/cycles/kernel/svm/svm_displace.h
===================================================================
--- trunk/blender/intern/cycles/kernel/svm/svm_displace.h	2013-05-09 14:01:42 UTC (rev 56620)
+++ trunk/blender/intern/cycles/kernel/svm/svm_displace.h	2013-05-09 14:05:37 UTC (rev 56621)
@@ -31,8 +31,8 @@
 	float3 Ry = cross(normal_in, sd->dP.dx);
 
 	/* get bump values */
-	uint c_offset, x_offset, y_offset, intensity_offset;
-	decode_node_uchar4(node.z, &c_offset, &x_offset, &y_offset, &intensity_offset);
+	uint c_offset, x_offset, y_offset, strength_offset;
+	decode_node_uchar4(node.z, &c_offset, &x_offset, &y_offset, &strength_offset);
 
 	float h_c = stack_load_float(stack, c_offset);
 	float h_x = stack_load_float(stack, x_offset);
@@ -41,14 +41,16 @@
 	/* compute surface gradient and determinant */
 	float det = dot(sd->dP.dx, Rx);
 	float3 surfgrad = (h_x - h_c)*Rx + (h_y - h_c)*Ry;
-	float intensity = stack_load_float(stack, intensity_offset);
 
-	surfgrad *= intensity;
 	float absdet = fabsf(det);
 
+	float strength = stack_load_float(stack, strength_offset);
+	strength = clamp(strength, 0.0f, 1.0f);
+
 	/* compute and output perturbed normal */
-	float3 outN = normalize(absdet*normal_in - signf(det)*surfgrad);
-	stack_store_float3(stack, node.w, outN);
+	float3 normal_out = normalize(absdet*normal_in - signf(det)*surfgrad);
+	normal_out = normalize(strength*normal_out + (1.0f - strength)*normal_in);
+	stack_store_float3(stack, node.w, normal_out);
 #endif
 }
 

Modified: trunk/blender/source/blender/nodes/shader/nodes/node_shader_bump.c
===================================================================
--- trunk/blender/source/blender/nodes/shader/nodes/node_shader_bump.c	2013-05-09 14:01:42 UTC (rev 56620)
+++ trunk/blender/source/blender/nodes/shader/nodes/node_shader_bump.c	2013-05-09 14:05:37 UTC (rev 56621)
@@ -36,7 +36,7 @@
 
 /* **************** BUMP ******************** */ 
 static bNodeSocketTemplate sh_node_bump_in[] = {
-	{ SOCK_FLOAT, 1, N_("Strength"),	0.1f, 0.0f, 0.0f, 0.0f, 0.0f, 10.0f},
+	{ SOCK_FLOAT, 1, N_("Strength"),	0.1f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f},
 	{ SOCK_FLOAT, 1, N_("Height"),		1.0f, 1.0f, 1.0f, 1.0f, -1000.0f, 1000.0f, PROP_NONE, SOCK_HIDE_VALUE},
 	{ SOCK_VECTOR, 1, N_("Normal"),	0.0f, 0.0f, 0.0f, 1.0f, -1.0f, 1.0f, PROP_NONE, SOCK_HIDE_VALUE},
 	{ -1, 0, "" }