Fix T61196: Mesh select ignores clipping

Select clipping now works when x-ray is disabled.

6 files changed, 97 insertions, 25 deletions

diff --git a/source/blender/editors/space_view3d/drawobject.c b/source/blender/editors/space_view3d/drawobject.c
index 2d2b898e3ec..7c1edaa5d81 100644
--- a/source/blender/editors/space_view3d/drawobject.c
+++ b/source/blender/editors/space_view3d/drawobject.c
@@ -184,50 +184,77 @@ bool view3d_camera_border_hack_test = false;
 
 /* ***************** BACKBUF SEL (BBS) ********* */
 
-static void bbs_mesh_verts(GPUBatch *batch, int offset)
+/** See #DRW_shgroup_world_clip_planes_from_rv3d, same function for draw manager. */
+static void bbs_world_clip_planes_from_rv3d(GPUBatch *batch, const float world_clip_planes[6][4])
+{
+	GPU_batch_uniform_4fv_array(batch, "WorldClipPlanes", 6, world_clip_planes[0]);
+}
+
+static void bbs_mesh_verts(GPUBatch *batch, int offset, const float world_clip_planes[6][4])
 {
 	GPU_point_size(UI_GetThemeValuef(TH_VERTEX_SIZE));
 
-	GPU_batch_program_set_builtin(batch, GPU_SHADER_3D_FLAT_SELECT_ID);
+	const eGPUShaderConfig shader_cfg = world_clip_planes ? GPU_SHADER_CFG_CLIPPED : GPU_SHADER_CFG_DEFAULT;
+	GPU_batch_program_set_builtin_with_config(batch, GPU_SHADER_3D_FLAT_SELECT_ID, shader_cfg);
 	GPU_batch_uniform_1ui(batch, "offset", offset);
+	if (world_clip_planes != NULL) {
+		bbs_world_clip_planes_from_rv3d(batch, world_clip_planes);
+	}
 	GPU_batch_draw(batch);
 }
 
-static void bbs_mesh_wire(GPUBatch *batch, int offset)
+static void bbs_mesh_wire(GPUBatch *batch, int offset, const float world_clip_planes[6][4])
 {
 	GPU_line_width(1.0f);
 	glProvokingVertex(GL_FIRST_VERTEX_CONVENTION);
 
-	GPU_batch_program_set_builtin(batch, GPU_SHADER_3D_FLAT_SELECT_ID);
+	const eGPUShaderConfig shader_cfg = world_clip_planes ? GPU_SHADER_CFG_CLIPPED : GPU_SHADER_CFG_DEFAULT;
+	GPU_batch_program_set_builtin_with_config(batch, GPU_SHADER_3D_FLAT_SELECT_ID, shader_cfg);
 	GPU_batch_uniform_1ui(batch, "offset", offset);
+	if (world_clip_planes != NULL) {
+		bbs_world_clip_planes_from_rv3d(batch, world_clip_planes);
+	}
 	GPU_batch_draw(batch);
 
 	glProvokingVertex(GL_LAST_VERTEX_CONVENTION);
 }
 
 /* two options, facecolors or black */
-static void bbs_mesh_face(GPUBatch *batch, const bool use_select)
+static void bbs_mesh_face(GPUBatch *batch, const bool use_select, const float world_clip_planes[6][4])
 {
 	if (use_select) {
-		GPU_batch_program_set_builtin(batch, GPU_SHADER_3D_FLAT_SELECT_ID);
+		const eGPUShaderConfig shader_cfg = world_clip_planes ? GPU_SHADER_CFG_CLIPPED : GPU_SHADER_CFG_DEFAULT;
+		GPU_batch_program_set_builtin_with_config(batch, GPU_SHADER_3D_FLAT_SELECT_ID, shader_cfg);
 		GPU_batch_uniform_1ui(batch, "offset", 1);
+		if (world_clip_planes != NULL) {
+			bbs_world_clip_planes_from_rv3d(batch, world_clip_planes);
+		}
 		GPU_batch_draw(batch);
 	}
 	else {
-		GPU_batch_program_set_builtin(batch, GPU_SHADER_3D_UNIFORM_SELECT_ID);
+		const eGPUShaderConfig shader_cfg = world_clip_planes ? GPU_SHADER_CFG_CLIPPED : GPU_SHADER_CFG_DEFAULT;
+		GPU_batch_program_set_builtin_with_config(batch, GPU_SHADER_3D_UNIFORM_SELECT_ID, shader_cfg);
 		GPU_batch_uniform_1ui(batch, "id", 0);
+		if (world_clip_planes != NULL) {
+			bbs_world_clip_planes_from_rv3d(batch, world_clip_planes);
+		}
 		GPU_batch_draw(batch);
 	}
 }
 
-static void bbs_mesh_face_dot(GPUBatch *batch)
+static void bbs_mesh_face_dot(GPUBatch *batch, const float world_clip_planes[6][4])
 {
-	GPU_batch_program_set_builtin(batch, GPU_SHADER_3D_FLAT_SELECT_ID);
+	const eGPUShaderConfig shader_cfg = world_clip_planes ? GPU_SHADER_CFG_CLIPPED : GPU_SHADER_CFG_DEFAULT;
+	GPU_batch_program_set_builtin_with_config(batch, GPU_SHADER_3D_FLAT_SELECT_ID, shader_cfg);
 	GPU_batch_uniform_1ui(batch, "offset", 1);
+	if (world_clip_planes != NULL) {
+		bbs_world_clip_planes_from_rv3d(batch, world_clip_planes);
+	}
 	GPU_batch_draw(batch);
 }
 
-static void bbs_mesh_solid_verts(Depsgraph *UNUSED(depsgraph), Scene *UNUSED(scene), Object *ob)
+static void bbs_mesh_solid_verts(
+        Depsgraph *UNUSED(depsgraph), Scene *UNUSED(scene), Object *ob, const float world_clip_planes[6][4])
 {
 	Mesh *me = ob->data;
 
@@ -236,13 +263,13 @@ static void bbs_mesh_solid_verts(Depsgraph *UNUSED(depsgraph), Scene *UNUSED(sce
 	DRW_mesh_batch_cache_create_requested(ob, me, NULL, false, true);
 
 	/* Only draw faces to mask out verts, we don't want their selection ID's. */
-	bbs_mesh_face(geom_faces, false);
-	bbs_mesh_verts(geom_verts, 1);
+	bbs_mesh_face(geom_faces, false, world_clip_planes);
+	bbs_mesh_verts(geom_verts, 1, world_clip_planes);
 
 	bm_vertoffs = me->totvert + 1;
 }
 
-static void bbs_mesh_solid_faces(Scene *UNUSED(scene), Object *ob)
+static void bbs_mesh_solid_faces(Scene *UNUSED(scene), Object *ob, const float world_clip_planes[6][4])
 {
 	Mesh *me = ob->data;
 	Mesh *me_orig = DEG_get_original_object(ob)->data;
@@ -251,7 +278,7 @@ static void bbs_mesh_solid_faces(Scene *UNUSED(scene), Object *ob)
 	GPUBatch *geom_faces = DRW_mesh_batch_cache_get_triangles_with_select_id(me);
 	DRW_mesh_batch_cache_create_requested(ob, me, NULL, false, use_hide);
 
-	bbs_mesh_face(geom_faces, true);
+	bbs_mesh_face(geom_faces, true, world_clip_planes);
 }
 
 void draw_object_backbufsel(
@@ -266,6 +293,11 @@ void draw_object_backbufsel(
 	GPU_matrix_mul(ob->obmat);
 	GPU_depth_test(true);
 
+	const float (*world_clip_planes)[4] = NULL;
+	if (rv3d->rflag & RV3D_CLIPPING) {
+		world_clip_planes = rv3d->clip;
+	}
+
 	switch (ob->type) {
 		case OB_MESH:
 			if (ob->mode & OB_MODE_EDIT) {
@@ -289,10 +321,10 @@ void draw_object_backbufsel(
 				}
 				DRW_mesh_batch_cache_create_requested(ob, me, NULL, false, true);
 
-				bbs_mesh_face(geom_faces, use_faceselect);
+				bbs_mesh_face(geom_faces, use_faceselect, world_clip_planes);
 
 				if (use_faceselect && draw_facedot) {
-					bbs_mesh_face_dot(geom_facedots);
+					bbs_mesh_face_dot(geom_facedots, world_clip_planes);
 				}
 
 				if (select_mode & SCE_SELECT_FACE)
@@ -305,7 +337,7 @@ void draw_object_backbufsel(
 
 				/* we draw edges if edge select mode */
 				if (select_mode & SCE_SELECT_EDGE) {
-					bbs_mesh_wire(geom_edges, bm_solidoffs);
+					bbs_mesh_wire(geom_edges, bm_solidoffs, world_clip_planes);
 					bm_wireoffs = bm_solidoffs + em->bm->totedge;
 				}
 				else {
@@ -317,7 +349,7 @@ void draw_object_backbufsel(
 
 				/* we draw verts if vert select mode. */
 				if (select_mode & SCE_SELECT_VERTEX) {
-					bbs_mesh_verts(geom_verts, bm_wireoffs);
+					bbs_mesh_verts(geom_verts, bm_wireoffs, world_clip_planes);
 					bm_vertoffs = bm_wireoffs + em->bm->totvert;
 				}
 				else {
@@ -332,10 +364,10 @@ void draw_object_backbufsel(
 				    /* currently vertex select supports weight paint and vertex paint*/
 				    ((ob->mode & OB_MODE_WEIGHT_PAINT) || (ob->mode & OB_MODE_VERTEX_PAINT)))
 				{
-					bbs_mesh_solid_verts(depsgraph, scene, ob);
+					bbs_mesh_solid_verts(depsgraph, scene, ob, world_clip_planes);
 				}
 				else {
-					bbs_mesh_solid_faces(scene, ob);
+					bbs_mesh_solid_faces(scene, ob, world_clip_planes);
 				}
 			}
 			break;
diff --git a/source/blender/editors/space_view3d/view3d_draw_legacy.c b/source/blender/editors/space_view3d/view3d_draw_legacy.c
index 7a358c46f75..4fa5bce3202 100644
--- a/source/blender/editors/space_view3d/view3d_draw_legacy.c
+++ b/source/blender/editors/space_view3d/view3d_draw_legacy.c
@@ -104,8 +104,13 @@
 
 /* ********* custom clipping *********** */
 
+/* Legacy 2.7x, now use shaders that use clip distance instead.
+ * Remove once clipping is working properly. */
+#define USE_CLIP_PLANES
+
 void ED_view3d_clipping_set(RegionView3D *rv3d)
 {
+#ifdef USE_CLIP_PLANES
 	double plane[4];
 	const unsigned int tot = (rv3d->viewlock & RV3D_BOXCLIP) ? 4 : 6;
 
@@ -113,20 +118,32 @@ void ED_view3d_clipping_set(RegionView3D *rv3d)
 		copy_v4db_v4fl(plane, rv3d->clip[a]);
 		glClipPlane(GL_CLIP_PLANE0 + a, plane);
 		glEnable(GL_CLIP_PLANE0 + a);
+		glEnable(GL_CLIP_DISTANCE0 + a);
+	}
+#else
+	for (unsigned a = 0; a < 6; a++) {
+		glEnable(GL_CLIP_DISTANCE0 + a);
 	}
+#endif
 }
 
 /* use these to temp disable/enable clipping when 'rv3d->rflag & RV3D_CLIPPING' is set */
 void ED_view3d_clipping_disable(void)
 {
 	for (unsigned a = 0; a < 6; a++) {
+#ifdef USE_CLIP_PLANES
 		glDisable(GL_CLIP_PLANE0 + a);
+#endif
+		glDisable(GL_CLIP_DISTANCE0 + a);
 	}
 }
 void ED_view3d_clipping_enable(void)
 {
 	for (unsigned a = 0; a < 6; a++) {
+#ifdef USE_CLIP_PLANES
 		glEnable(GL_CLIP_PLANE0 + a);
+#endif
+		glEnable(GL_CLIP_DISTANCE0 + a);
 	}
 }
 
diff --git a/source/blender/gpu/GPU_batch.h b/source/blender/gpu/GPU_batch.h
index 4311b73d1ef..9637ef74b8c 100644
--- a/source/blender/gpu/GPU_batch.h
+++ b/source/blender/gpu/GPU_batch.h
@@ -122,7 +122,11 @@ int GPU_batch_vertbuf_add_ex(GPUBatch *, GPUVertBuf *, bool own_vbo);
 
 void GPU_batch_program_set_no_use(GPUBatch *, uint32_t program, const GPUShaderInterface *);
 void GPU_batch_program_set(GPUBatch *, uint32_t program, const GPUShaderInterface *);
-void GPU_batch_program_set_builtin(GPUBatch *batch, eGPUBuiltinShader shader_id);
+void GPU_batch_program_set_shader(GPUBatch *, GPUShader *shader);
+void GPU_batch_program_set_builtin(
+        GPUBatch *batch, eGPUBuiltinShader shader_id);
+void GPU_batch_program_set_builtin_with_config(
+        GPUBatch *batch, eGPUBuiltinShader shader_id, eGPUShaderConfig shader_cfg);
 /* Entire batch draws with one shader program, but can be redrawn later with another program. */
 /* Vertex shader's inputs must be compatible with the batch's vertex format. */
 
diff --git a/source/blender/gpu/intern/gpu_batch.c b/source/blender/gpu/intern/gpu_batch.c
index 66b17fa9704..a095f85d883 100644
--- a/source/blender/gpu/intern/gpu_batch.c
+++ b/source/blender/gpu/intern/gpu_batch.c
@@ -664,12 +664,23 @@ void GPU_draw_primitive(GPUPrimType prim_type, int v_count)
 /** \name Utilities
  * \{ */
 
-void GPU_batch_program_set_builtin(GPUBatch *batch, eGPUBuiltinShader shader_id)
+void GPU_batch_program_set_shader(GPUBatch *batch, GPUShader *shader)
+{
+	GPU_batch_program_set(batch, shader->program, shader->interface);
+}
+
+void GPU_batch_program_set_builtin_with_config(
+        GPUBatch *batch, eGPUBuiltinShader shader_id, eGPUShaderConfig shader_cfg)
 {
-	GPUShader *shader = GPU_shader_get_builtin_shader(shader_id);
+	GPUShader *shader = GPU_shader_get_builtin_shader_with_config(shader_id, shader_cfg);
 	GPU_batch_program_set(batch, shader->program, shader->interface);
 }
 
+void GPU_batch_program_set_builtin(GPUBatch *batch, eGPUBuiltinShader shader_id)
+{
+	GPU_batch_program_set_builtin_with_config(batch, shader_id, GPU_SHADER_CFG_DEFAULT);
+}
+
 /** \} */
 
 /* -------------------------------------------------------------------- */
diff --git a/source/blender/gpu/intern/gpu_shader.c b/source/blender/gpu/intern/gpu_shader.c
index 99f4df29418..2236ea33842 100644
--- a/source/blender/gpu/intern/gpu_shader.c
+++ b/source/blender/gpu/intern/gpu_shader.c
@@ -1219,7 +1219,9 @@ GPUShader *GPU_shader_get_builtin_shader_with_config(
 			                GPU_SHADER_3D_GROUNDLINE,
 			                GPU_SHADER_3D_GROUNDPOINT,
 			                GPU_SHADER_DISTANCE_LINES,
-			                GPU_SHADER_INSTANCE_EDGES_VARIYING_COLOR));
+			                GPU_SHADER_INSTANCE_EDGES_VARIYING_COLOR,
+			                GPU_SHADER_3D_FLAT_SELECT_ID,
+			                GPU_SHADER_3D_UNIFORM_SELECT_ID));
 			const char *world_clip_lib = datatoc_gpu_shader_cfg_world_clip_lib_glsl;
 			const char *world_clip_def = "#define USE_WORLD_CLIP_PLANES\n";
 			/* In rare cases geometry shaders calculate clipping themselves. */
diff --git a/source/blender/gpu/shaders/gpu_shader_3D_selection_id_vert.glsl b/source/blender/gpu/shaders/gpu_shader_3D_selection_id_vert.glsl
index 9c6be69efce..aa544ea82ee 100644
--- a/source/blender/gpu/shaders/gpu_shader_3D_selection_id_vert.glsl
+++ b/source/blender/gpu/shaders/gpu_shader_3D_selection_id_vert.glsl
@@ -20,5 +20,11 @@ void main()
 		(((color + offset) >> 24)             ) * (1.0f / 255.0f));
 #endif
 
-	gl_Position = ModelViewProjectionMatrix * vec4(pos, 1.0);
+	vec4 pos_4d = vec4(pos, 1.0);
+	gl_Position = ModelViewProjectionMatrix * pos_4d;
+
+#ifdef USE_WORLD_CLIP_PLANES
+	/* Warning: ModelMatrix is typically used but select drawing is different. */
+	world_clip_planes_calc_clip_distance(pos);
+#endif
 }