DRW: use clipping for depth buffer

Object selection now supports clipping.

1 files changed, 28 insertions, 6 deletions

diff --git a/source/blender/draw/engines/basic/basic_engine.c b/source/blender/draw/engines/basic/basic_engine.c
index 0ee6853409a..7f4da54e63d 100644
--- a/source/blender/draw/engines/basic/basic_engine.c
+++ b/source/blender/draw/engines/basic/basic_engine.c
@@ -66,11 +66,15 @@ typedef struct BASIC_Data {
 	BASIC_StorageList *stl;
 } BASIC_Data;
 
+typedef struct BASIC_Shaders {
+	/* Depth Pre Pass */
+	struct GPUShader *depth;
+} BASIC_Shaders;
+
 /* *********** STATIC *********** */
 
 static struct {
-	/* Depth Pre Pass */
-	struct GPUShader *depth_sh;
+	BASIC_Shaders sh_data[DRW_SHADER_SLOT_LEN];
 } e_data = {NULL}; /* Engine data */
 
 typedef struct BASIC_PrivateData {
@@ -83,9 +87,12 @@ typedef struct BASIC_PrivateData {
 
 static void basic_engine_init(void *UNUSED(vedata))
 {
+	const DRWContextState *draw_ctx = DRW_context_state_get();
+	BASIC_Shaders *sh_data = &e_data.sh_data[draw_ctx->shader_slot];
+
 	/* Depth prepass */
-	if (!e_data.depth_sh) {
-		e_data.depth_sh = DRW_shader_create_3D_depth_only();
+	if (!sh_data->depth) {
+		sh_data->depth = DRW_shader_create_3D_depth_only(draw_ctx->shader_slot);
 	}
 }
 
@@ -94,6 +101,15 @@ static void basic_cache_init(void *vedata)
 	BASIC_PassList *psl = ((BASIC_Data *)vedata)->psl;
 	BASIC_StorageList *stl = ((BASIC_Data *)vedata)->stl;
 
+	const DRWContextState *draw_ctx = DRW_context_state_get();
+	BASIC_Shaders *sh_data = &e_data.sh_data[draw_ctx->shader_slot];
+	const RegionView3D *rv3d = draw_ctx->rv3d;
+	const bool is_clip = (rv3d->rflag & RV3D_CLIPPING) != 0;
+
+	if (is_clip) {
+		DRW_state_clip_planes_set_from_rv3d(draw_ctx->rv3d);
+	}
+
 	if (!stl->g_data) {
 		/* Alloc transient pointers */
 		stl->g_data = MEM_mallocN(sizeof(*stl->g_data), __func__);
@@ -102,12 +118,18 @@ static void basic_cache_init(void *vedata)
 	{
 		psl->depth_pass = DRW_pass_create(
 		        "Depth Pass", DRW_STATE_WRITE_DEPTH | DRW_STATE_DEPTH_LESS_EQUAL | DRW_STATE_WIRE);
-		stl->g_data->depth_shgrp = DRW_shgroup_create(e_data.depth_sh, psl->depth_pass);
+		stl->g_data->depth_shgrp = DRW_shgroup_create(sh_data->depth, psl->depth_pass);
+		if (rv3d->rflag & RV3D_CLIPPING) {
+			DRW_shgroup_world_clip_planes_from_rv3d(stl->g_data->depth_shgrp, rv3d);
+		}
 
 		psl->depth_pass_cull = DRW_pass_create(
 		        "Depth Pass Cull",
 		        DRW_STATE_WRITE_DEPTH | DRW_STATE_DEPTH_LESS_EQUAL | DRW_STATE_CULL_BACK);
-		stl->g_data->depth_shgrp_cull = DRW_shgroup_create(e_data.depth_sh, psl->depth_pass_cull);
+		stl->g_data->depth_shgrp_cull = DRW_shgroup_create(sh_data->depth, psl->depth_pass_cull);
+		if (rv3d->rflag & RV3D_CLIPPING) {
+			DRW_shgroup_world_clip_planes_from_rv3d(stl->g_data->depth_shgrp_cull, rv3d);
+		}
 	}
 }