DRW: Remove ModelViewMatrix Usage

3 files changed, 16 insertions, 10 deletions

diff --git a/source/blender/draw/engines/workbench/shaders/workbench_volume_frag.glsl b/source/blender/draw/engines/workbench/shaders/workbench_volume_frag.glsl
index a1c269d5a65..cef405d12d3 100644
--- a/source/blender/draw/engines/workbench/shaders/workbench_volume_frag.glsl
+++ b/source/blender/draw/engines/workbench/shaders/workbench_volume_frag.glsl
@@ -1,8 +1,7 @@
 
-uniform mat4 ProjectionMatrix;
-uniform mat4 ModelMatrixInverse;
-uniform mat4 ModelViewMatrixInverse;
 uniform mat4 ModelMatrix;
+uniform mat4 ModelMatrixInverse;
+
 uniform vec3 OrcoTexCoFactors[2];
 
 uniform sampler2D depthBuffer;
@@ -219,9 +218,11 @@ void main()
   vec3 vs_ray_dir = (is_persp) ? (vs_ray_end - vs_ray_ori) : vec3(0.0, 0.0, -1.0);
   vs_ray_dir /= abs(vs_ray_dir.z);
 
-  vec3 ls_ray_dir = mat3(ModelViewMatrixInverse) * vs_ray_dir * OrcoTexCoFactors[1] * 2.0;
-  vec3 ls_ray_ori = (ModelViewMatrixInverse * vec4(vs_ray_ori, 1.0)).xyz;
-  vec3 ls_ray_end = (ModelViewMatrixInverse * vec4(vs_ray_end, 1.0)).xyz;
+  /* TODO(fclem) Precompute the matrix/ */
+  vec3 ls_ray_dir = vs_ray_dir * OrcoTexCoFactors[1] * 2.0;
+  ls_ray_dir = mat3(ModelMatrixInverse) * (mat3(ViewMatrixInverse) * ls_ray_dir);
+  vec3 ls_ray_ori = point_view_to_object(vs_ray_ori);
+  vec3 ls_ray_end = point_view_to_object(vs_ray_end);
 
   ls_ray_ori = (OrcoTexCoFactors[0] + ls_ray_ori * OrcoTexCoFactors[1]) * 2.0 - 1.0;
   ls_ray_end = (OrcoTexCoFactors[0] + ls_ray_end * OrcoTexCoFactors[1]) * 2.0 - 1.0;
diff --git a/source/blender/draw/engines/workbench/shaders/workbench_volume_vert.glsl b/source/blender/draw/engines/workbench/shaders/workbench_volume_vert.glsl
index 7a418243fd3..1834173fee9 100644
--- a/source/blender/draw/engines/workbench/shaders/workbench_volume_vert.glsl
+++ b/source/blender/draw/engines/workbench/shaders/workbench_volume_vert.glsl
@@ -1,5 +1,6 @@
 
-uniform mat4 ModelViewProjectionMatrix;
+uniform mat4 ModelMatrix;
+
 uniform vec3 OrcoTexCoFactors[2];
 uniform float slicePosition;
 uniform int sliceAxis; /* -1 is no slice, 0 is X, 1 is Y, 2 is Z. */
@@ -29,5 +30,5 @@ void main()
   vec3 final_pos = pos;
 #endif
   final_pos = ((final_pos * 0.5 + 0.5) - OrcoTexCoFactors[0]) / OrcoTexCoFactors[1];
-  gl_Position = ModelViewProjectionMatrix * vec4(final_pos, 1.0);
+  gl_Position = point_object_to_ndc(final_pos);
 }
diff --git a/source/blender/draw/engines/workbench/workbench_volume.c b/source/blender/draw/engines/workbench/workbench_volume.c
index accc7e91576..d2f19f57dcf 100644
--- a/source/blender/draw/engines/workbench/workbench_volume.c
+++ b/source/blender/draw/engines/workbench/workbench_volume.c
@@ -53,6 +53,7 @@ static struct {
 
 extern char datatoc_workbench_volume_vert_glsl[];
 extern char datatoc_workbench_volume_frag_glsl[];
+extern char datatoc_common_view_lib_glsl[];
 
 static GPUShader *volume_shader_get(bool slice, bool coba, bool cubic)
 {
@@ -77,8 +78,11 @@ static GPUShader *volume_shader_get(bool slice, bool coba, bool cubic)
     char *defines = BLI_dynstr_get_cstring(ds);
     BLI_dynstr_free(ds);
 
-    e_data.volume_sh[id] = DRW_shader_create(
-        datatoc_workbench_volume_vert_glsl, NULL, datatoc_workbench_volume_frag_glsl, defines);
+    e_data.volume_sh[id] = DRW_shader_create_with_lib(datatoc_workbench_volume_vert_glsl,
+                                                      NULL,
+                                                      datatoc_workbench_volume_frag_glsl,
+                                                      datatoc_common_view_lib_glsl,
+                                                      defines);
 
     MEM_freeN(defines);
   }