GPU: Remove GPU_INVERSE_NORMAL_MATRIX

The end goal for this is to lower the number of needed matrices.

This also cleanup some uneeded transformation.

5 files changed, 27 insertions, 31 deletions

diff --git a/source/blender/gpu/GPU_material.h b/source/blender/gpu/GPU_material.h
index da61dc76422..1640209c717 100644
--- a/source/blender/gpu/GPU_material.h
+++ b/source/blender/gpu/GPU_material.h
@@ -107,7 +107,7 @@ typedef enum eGPUBuiltin {
   GPU_VOLUME_TEMPERATURE = (1 << 18),
   GPU_BARYCENTRIC_TEXCO = (1 << 19),
   GPU_BARYCENTRIC_DIST = (1 << 20),
-  GPU_INVERSE_NORMAL_MATRIX = (1 << 21),
+  GPU_WORLD_NORMAL = (1 << 21),
 } eGPUBuiltin;
 
 typedef enum eGPUMatFlag {
diff --git a/source/blender/gpu/GPU_shader_interface.h b/source/blender/gpu/GPU_shader_interface.h
index 563868311c2..1b10de45cee 100644
--- a/source/blender/gpu/GPU_shader_interface.h
+++ b/source/blender/gpu/GPU_shader_interface.h
@@ -45,7 +45,6 @@ typedef enum {
   GPU_UNIFORM_VIEWPROJECTION_INV, /* mat4 ViewProjectionMatrixInverse */
 
   GPU_UNIFORM_NORMAL,      /* mat3 NormalMatrix */
-  GPU_UNIFORM_NORMAL_INV,  /* mat3 NormalMatrixInverse */
   GPU_UNIFORM_WORLDNORMAL, /* mat3 WorldNormalMatrix */
   GPU_UNIFORM_CAMERATEXCO, /* vec4 CameraTexCoFactors */
   GPU_UNIFORM_ORCO,        /* vec3 OrcoTexCoFactors[] */
diff --git a/source/blender/gpu/intern/gpu_codegen.c b/source/blender/gpu/intern/gpu_codegen.c
index a77bba5ab86..310c57fdbee 100644
--- a/source/blender/gpu/intern/gpu_codegen.c
+++ b/source/blender/gpu/intern/gpu_codegen.c
@@ -520,9 +520,6 @@ const char *GPU_builtin_name(eGPUBuiltin builtin)
   else if (builtin == GPU_INVERSE_OBJECT_MATRIX) {
     return "unfinvobmat";
   }
-  else if (builtin == GPU_INVERSE_NORMAL_MATRIX) {
-    return "unfinvnormat";
-  }
   else if (builtin == GPU_LOC_TO_VIEW_MATRIX) {
     return "unflocaltoviewmat";
   }
@@ -532,6 +529,9 @@ const char *GPU_builtin_name(eGPUBuiltin builtin)
   else if (builtin == GPU_VIEW_POSITION) {
     return "varposition";
   }
+  else if (builtin == GPU_WORLD_NORMAL) {
+    return "varwnormal";
+  }
   else if (builtin == GPU_VIEW_NORMAL) {
     return "varnormal";
   }
@@ -786,15 +786,15 @@ static void codegen_call_functions(DynStr *ds, ListBase *nodes, GPUOutput *final
         else if (input->builtin == GPU_INVERSE_OBJECT_MATRIX) {
           BLI_dynstr_append(ds, "objinv");
         }
-        else if (input->builtin == GPU_INVERSE_NORMAL_MATRIX) {
-          BLI_dynstr_append(ds, "norinv");
-        }
         else if (input->builtin == GPU_VIEW_POSITION) {
           BLI_dynstr_append(ds, "viewposition");
         }
         else if (input->builtin == GPU_VIEW_NORMAL) {
           BLI_dynstr_append(ds, "facingnormal");
         }
+        else if (input->builtin == GPU_WORLD_NORMAL) {
+          BLI_dynstr_append(ds, "facingwnormal");
+        }
         else {
           BLI_dynstr_append(ds, GPU_builtin_name(input->builtin));
         }
@@ -879,9 +879,6 @@ static char *code_generate_fragment(GPUMaterial *material,
   if (builtins & GPU_INVERSE_OBJECT_MATRIX) {
     BLI_dynstr_append(ds, "\t#define objinv ModelMatrixInverse\n");
   }
-  if (builtins & GPU_INVERSE_NORMAL_MATRIX) {
-    BLI_dynstr_append(ds, "\t#define norinv NormalMatrixInverse\n");
-  }
   if (builtins & GPU_INVERSE_VIEW_MATRIX) {
     BLI_dynstr_append(ds, "\t#define viewinv ViewMatrixInverse\n");
   }
@@ -897,9 +894,22 @@ static char *code_generate_fragment(GPUMaterial *material,
     BLI_dynstr_append(ds, "\tworld_normals_get(n);\n");
     BLI_dynstr_append(ds, "\tvec3 facingnormal = transform_direction(ViewMatrix, n);\n");
     BLI_dynstr_append(ds, "#else\n");
-    BLI_dynstr_append(ds, "\tvec3 facingnormal = gl_FrontFacing? viewNormal: -viewNormal;\n");
+    BLI_dynstr_append(ds, "\tvec3 facingnormal = gl_FrontFacing ? viewNormal: -viewNormal;\n");
     BLI_dynstr_append(ds, "#endif\n");
   }
+  if (builtins & GPU_WORLD_NORMAL) {
+    BLI_dynstr_append(ds, "\tvec3 facingwnormal;\n");
+    if (builtins & GPU_VIEW_NORMAL) {
+      BLI_dynstr_append(ds, "#ifdef HAIR_SHADER\n");
+      BLI_dynstr_append(ds, "\tfacingwnormal = n;\n");
+      BLI_dynstr_append(ds, "#else\n");
+      BLI_dynstr_append(ds, "\tworld_normals_get(facingwnormal);\n");
+      BLI_dynstr_append(ds, "#endif\n");
+    }
+    else {
+      BLI_dynstr_append(ds, "\tworld_normals_get(facingwnormal);\n");
+    }
+  }
   if (builtins & GPU_VIEW_POSITION) {
     BLI_dynstr_append(ds, "\t#define viewposition viewPosition\n");
   }
diff --git a/source/blender/gpu/intern/gpu_shader_interface.c b/source/blender/gpu/intern/gpu_shader_interface.c
index 1c9e9e42bcc..207a218b5d1 100644
--- a/source/blender/gpu/intern/gpu_shader_interface.c
+++ b/source/blender/gpu/intern/gpu_shader_interface.c
@@ -61,7 +61,6 @@ static const char *BuiltinUniform_name(GPUUniformBuiltin u)
       [GPU_UNIFORM_VIEWPROJECTION_INV] = "ViewProjectionMatrixInverse",
 
       [GPU_UNIFORM_NORMAL] = "NormalMatrix",
-      [GPU_UNIFORM_NORMAL_INV] = "NormalMatrixInverse",
       [GPU_UNIFORM_WORLDNORMAL] = "WorldNormalMatrix",
       [GPU_UNIFORM_CAMERATEXCO] = "CameraTexCoFactors",
       [GPU_UNIFORM_ORCO] = "OrcoTexCoFactors",
diff --git a/source/blender/gpu/shaders/gpu_shader_material.glsl b/source/blender/gpu/shaders/gpu_shader_material.glsl
index 1cbf58f9d16..ca05a9b6238 100644
--- a/source/blender/gpu/shaders/gpu_shader_material.glsl
+++ b/source/blender/gpu/shaders/gpu_shader_material.glsl
@@ -2,7 +2,6 @@
 uniform mat4 ModelViewMatrix;
 uniform mat4 ModelViewMatrixInverse;
 uniform mat3 NormalMatrix;
-uniform mat3 NormalMatrixInverse;
 
 #ifndef USE_ATTR
 uniform mat4 ModelMatrix;
@@ -204,9 +203,9 @@ void direction_transform_m4v3(vec3 vin, mat4 mat, out vec3 vout)
   vout = (mat * vec4(vin, 0.0)).xyz;
 }
 
-void mat3_mul(vec3 vin, mat3 mat, out vec3 vout)
+void normal_transform_transposed_m4v3(vec3 vin, mat4 mat, out vec3 vout)
 {
-  vout = mat * vin;
+  vout = transpose(mat3(mat)) * vin;
 }
 
 void point_transform_m4v3(vec3 vin, mat4 mat, out vec3 vout)
@@ -2092,9 +2091,7 @@ void generated_texco(vec3 I, vec3 attr_orco, out vec3 generated)
 }
 
 void node_tex_coord(vec3 I,
-                    vec3 N,
-                    mat4 viewinvmat,
-                    mat4 obinvmat,
+                    vec3 wN,
                     vec4 camerafac,
                     vec3 attr_orco,
                     vec3 attr_uv,
@@ -2107,22 +2104,17 @@ void node_tex_coord(vec3 I,
                     out vec3 reflection)
 {
   generated = attr_orco;
-  normal = normalize(NormalMatrixInverse * N);
+  normal = normalize(transform_normal_world_to_object(wN));
   uv = attr_uv;
-  object = (obinvmat * (viewinvmat * vec4(I, 1.0))).xyz;
+  object = transform_point_view_to_object(I);
   camera = vec3(I.xy, -I.z);
   vec4 projvec = ProjectionMatrix * vec4(I, 1.0);
   window = vec3(mtex_2d_mapping(projvec.xyz / projvec.w).xy * camerafac.xy + camerafac.zw, 0.0);
-
-  vec3 shade_I = (ProjectionMatrix[3][3] == 0.0) ? normalize(I) : vec3(0.0, 0.0, -1.0);
-  vec3 view_reflection = reflect(shade_I, normalize(N));
-  reflection = (viewinvmat * vec4(view_reflection, 0.0)).xyz;
+  reflection = reflect(cameraVec, normalize(wN));
 }
 
 void node_tex_coord_background(vec3 I,
                                vec3 N,
-                               mat4 viewinvmat,
-                               mat4 obinvmat,
                                vec4 camerafac,
                                vec3 attr_orco,
                                vec3 attr_uv,
@@ -2141,11 +2133,7 @@ void node_tex_coord_background(vec3 I,
 
   co = normalize(co);
 
-#if defined(WORLD_BACKGROUND) || defined(PROBE_CAPTURE)
   vec3 coords = (ViewMatrixInverse * co).xyz;
-#else
-  vec3 coords = (ModelViewMatrixInverse * co).xyz;
-#endif
 
   generated = coords;
   normal = -coords;