TexturePaint: Missing Texture Depth Test

Depth testing was off as it used the precomputed ModelView matrix. As
draw engines currently use a different approach the depth was sometimes
a bit off making the color disappear.

This change will use a different vertex shader that will write the
correct depth. I expected the same change to be needed in the bone
selection overlay but was not able to reproduce it.

Reviewed By: fclem

Maniphest Tasks: T64615

Differential Revision: https://developer.blender.org/D5006

1 files changed, 10 insertions, 5 deletions

diff --git a/source/blender/draw/modes/paint_texture_mode.c b/source/blender/draw/modes/paint_texture_mode.c
index 66e2cf7122d..a31efccda88 100644
--- a/source/blender/draw/modes/paint_texture_mode.c
+++ b/source/blender/draw/modes/paint_texture_mode.c
@@ -47,6 +47,7 @@ extern char datatoc_paint_texture_frag_glsl[];
 extern char datatoc_paint_wire_vert_glsl[];
 extern char datatoc_paint_wire_frag_glsl[];
 extern char datatoc_paint_face_vert_glsl[];
+extern char datatoc_paint_face_selection_vert_glsl[];
 
 extern char datatoc_gpu_shader_uniform_color_frag_glsl[];
 
@@ -144,8 +145,14 @@ static void PAINT_TEXTURE_engine_init(void *vedata)
 
   if (!sh_data->fallback) {
     const GPUShaderConfigData *sh_cfg_data = &GPU_shader_cfg_data[draw_ctx->sh_cfg];
-    sh_data->fallback = GPU_shader_get_builtin_shader_with_config(GPU_SHADER_3D_UNIFORM_COLOR,
-                                                                  draw_ctx->sh_cfg);
+    sh_data->fallback = GPU_shader_create_from_arrays({
+        .vert = (const char *[]){sh_cfg_data->lib,
+                                 datatoc_common_view_lib_glsl,
+                                 datatoc_paint_face_vert_glsl,
+                                 NULL},
+        .frag = (const char *[]){datatoc_gpu_shader_uniform_color_frag_glsl, NULL},
+        .defs = (const char *[]){sh_cfg_data->def, NULL},
+    });
 
     sh_data->image = GPU_shader_create_from_arrays({
         .vert = (const char *[]){sh_cfg_data->lib,
@@ -180,7 +187,7 @@ static void PAINT_TEXTURE_engine_init(void *vedata)
     sh_data->face_select_overlay = GPU_shader_create_from_arrays({
         .vert = (const char *[]){sh_cfg_data->lib,
                                  datatoc_common_view_lib_glsl,
-                                 datatoc_paint_face_vert_glsl,
+                                 datatoc_paint_face_selection_vert_glsl,
                                  NULL},
         .frag = (const char *[]){datatoc_common_view_lib_glsl,
                                  datatoc_gpu_shader_uniform_color_frag_glsl,
@@ -433,8 +440,6 @@ static void PAINT_TEXTURE_engine_free(void)
 {
   for (int sh_data_index = 0; sh_data_index < ARRAY_SIZE(e_data.sh_data); sh_data_index++) {
     PAINT_TEXTURE_Shaders *sh_data = &e_data.sh_data[sh_data_index];
-    /* Don't free builtins. */
-    sh_data->fallback = NULL;
     GPUShader **sh_data_as_array = (GPUShader **)sh_data;
     for (int i = 0; i < (sizeof(PAINT_TEXTURE_Shaders) / sizeof(GPUShader *)); i++) {
       DRW_SHADER_FREE_SAFE(sh_data_as_array[i]);