From: divverent <divverent@d7cf8633-e32d-0410-b094-e92efae38249>
Date: Sun, 20 Jan 2013 21:11:58 +0000 (+0000)
Subject: Fix typos in GPU skeletal; explain the crossproduct hack
X-Git-Tag: xonotic-v0.8.0~96^2~155
X-Git-Url: https://git.rm.cloudns.org/?a=commitdiff_plain;h=c9f91aea3b2cb789ece619699e7f41db9b88443a;p=xonotic%2Fdarkplaces.git

Fix typos in GPU skeletal; explain the crossproduct hack

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@11883 d7cf8633-e32d-0410-b094-e92efae38249
---

diff --git a/gl_rmain.c b/gl_rmain.c
index 7a10c491..ef397326 100644
--- a/gl_rmain.c
+++ b/gl_rmain.c
@@ -9293,9 +9293,9 @@ void RSurf_PrepareVerticesForBatch(int batchneed, int texturenumsurfaces, const
 			if (vn)
 			{
 				// the normal transformation matrix is a set of cross products...
-				CrossProduct(m[1], m[0], n[0]);
+				CrossProduct(m[1], m[2], n[0]);
 				CrossProduct(m[2], m[0], n[1]);
-				CrossProduct(m[0], m[1], n[2]);
+				CrossProduct(m[0], m[1], n[2]); // is actually transpose(inverse(m)) * det(m)
 				VectorCopy(vn, tn);
 				vn[0] = tn[0] * n[0][0] + tn[1] * n[0][1] + tn[2] * n[0][2];
 				vn[1] = tn[0] * n[1][0] + tn[1] * n[1][1] + tn[2] * n[1][2];
diff --git a/shader_glsl.h b/shader_glsl.h
index ac0dd80a..cc0f88b1 100644
--- a/shader_glsl.h
+++ b/shader_glsl.h
@@ -572,7 +572,7 @@
 "	vec4 SkeletalMatrix2 = Skeletal_Transform12[si1.x] * sw.x + Skeletal_Transform12[si1.y] * sw.y + Skeletal_Transform12[si1.z] * sw.z + Skeletal_Transform12[si1.w] * sw.w;\n"
 "	vec4 SkeletalMatrix3 = Skeletal_Transform12[si2.x] * sw.x + Skeletal_Transform12[si2.y] * sw.y + Skeletal_Transform12[si2.z] * sw.z + Skeletal_Transform12[si2.w] * sw.w;\n"
 "	mat4 SkeletalMatrix = mat4(SkeletalMatrix1, SkeletalMatrix2, SkeletalMatrix3, vec4(0.0, 0.0, 0.0, 1.0));\n"
-"	mat3 SkeletalNormalMatrix = mat3(cross(SkeletalMatrix[1].xyz, SkeletalMatrix[0].xyz), cross(SkeletalMatrix[2].xyz, SkeletalMatrix[0].xyz), cross(SkeletalMatrix[0].xyz, SkeletalMatrix[1].xyz));\n"
+"	mat3 SkeletalNormalMatrix = mat3(cross(SkeletalMatrix[1].xyz, SkeletalMatrix[2].xyz), cross(SkeletalMatrix[2].xyz, SkeletalMatrix[0].xyz), cross(SkeletalMatrix[0].xyz, SkeletalMatrix[1].xyz)); // is actually transpose(inverse(mat3(SkeletalMatrix))) * det(mat3(SkeletalMatrix))\n"
 "	vec4 SkeletalVertex = Attrib_Position * SkeletalMatrix;\n"
 "	vec3 SkeletalSVector = normalize(Attrib_TexCoord1.xyz * SkeletalNormalMatrix);\n"
 "	vec3 SkeletalTVector = normalize(Attrib_TexCoord2.xyz * SkeletalNormalMatrix);\n"
@@ -1070,7 +1070,7 @@
 "	vec4 SkeletalMatrix2 = Skeletal_Transform12[si1.x] * sw.x + Skeletal_Transform12[si1.y] * sw.y + Skeletal_Transform12[si1.z] * sw.z + Skeletal_Transform12[si1.w] * sw.w;\n"
 "	vec4 SkeletalMatrix3 = Skeletal_Transform12[si2.x] * sw.x + Skeletal_Transform12[si2.y] * sw.y + Skeletal_Transform12[si2.z] * sw.z + Skeletal_Transform12[si2.w] * sw.w;\n"
 "	mat4 SkeletalMatrix = mat4(SkeletalMatrix1, SkeletalMatrix2, SkeletalMatrix3, vec4(0.0, 0.0, 0.0, 1.0));\n"
-"	mat3 SkeletalNormalMatrix = mat3(cross(SkeletalMatrix[1].xyz, SkeletalMatrix[0].xyz), cross(SkeletalMatrix[2].xyz, SkeletalMatrix[0].xyz), cross(SkeletalMatrix[0].xyz, SkeletalMatrix[1].xyz));\n"
+"	mat3 SkeletalNormalMatrix = mat3(cross(SkeletalMatrix[1].xyz, SkeletalMatrix[2].xyz), cross(SkeletalMatrix[2].xyz, SkeletalMatrix[0].xyz), cross(SkeletalMatrix[0].xyz, SkeletalMatrix[1].xyz)); // is actually transpose(inverse(mat3(SkeletalMatrix))) * det(mat3(SkeletalMatrix))\n"
 "	vec4 SkeletalVertex = Attrib_Position * SkeletalMatrix;\n"
 "	vec3 SkeletalSVector = normalize(Attrib_TexCoord1.xyz * SkeletalNormalMatrix);\n"
 "	vec3 SkeletalTVector = normalize(Attrib_TexCoord2.xyz * SkeletalNormalMatrix);\n"
@@ -1260,7 +1260,7 @@
 "	mat4 SkeletalMatrix = mat4(SkeletalMatrix1, SkeletalMatrix2, SkeletalMatrix3, vec4(0.0, 0.0, 0.0, 1.0));\n"
 "//	ivec4 si = ivec4(Attrib_SkeletalIndex);\n"
 "//	mat4 SkeletalMatrix = Skeletal_Transform[si.x] * Attrib_SkeletalWeight.x + Skeletal_Transform[si.y] * Attrib_SkeletalWeight.y + Skeletal_Transform[si.z] * Attrib_SkeletalWeight.z + Skeletal_Transform[si.w] * Attrib_SkeletalWeight.w;\n"
-"	mat3 SkeletalNormalMatrix = mat3(cross(SkeletalMatrix[1].xyz, SkeletalMatrix[0].xyz), cross(SkeletalMatrix[2].xyz, SkeletalMatrix[0].xyz), cross(SkeletalMatrix[0].xyz, SkeletalMatrix[1].xyz));\n"
+"	mat3 SkeletalNormalMatrix = mat3(cross(SkeletalMatrix[1].xyz, SkeletalMatrix[2].xyz), cross(SkeletalMatrix[2].xyz, SkeletalMatrix[0].xyz), cross(SkeletalMatrix[0].xyz, SkeletalMatrix[1].xyz)); // is actually transpose(inverse(mat3(SkeletalMatrix))) * det(mat3(SkeletalMatrix))\n"
 "	vec4 SkeletalVertex = Attrib_Position * SkeletalMatrix;\n"
 "	SkeletalVertex.w = 1.0;\n"
 "	vec3 SkeletalSVector = normalize(Attrib_TexCoord1.xyz * SkeletalNormalMatrix);\n"