1 files changed, 234 insertions, 0 deletions

diff --git a/source/blender/draw/engines/external/external_engine.c b/source/blender/draw/engines/external/external_engine.c
new file mode 100644
index 00000000000..ec0141953fe
--- /dev/null
+++ b/source/blender/draw/engines/external/external_engine.c
@@ -0,0 +1,234 @@
+/*
+ * Copyright 2017, Blender Foundation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Contributor(s): Blender Institute
+ *
+ */
+
+/** \file external_engine.c
+ *  \ingroup draw_engine
+ *
+ * Base engine for external render engines.
+ * We use it for depth and non-mesh objects.
+ */
+
+#include "DRW_render.h"
+
+#include "DNA_screen_types.h"
+#include "DNA_view3d_types.h"
+
+#include "BKE_icons.h"
+#include "BKE_idprop.h"
+#include "BKE_main.h"
+
+#include "ED_view3d.h"
+#include "ED_screen.h"
+
+#include "GPU_glew.h"
+#include "GPU_matrix.h"
+#include "GPU_shader.h"
+#include "GPU_viewport.h"
+
+#include "external_engine.h"
+/* Shaders */
+
+#define EXTERNAL_ENGINE "BLENDER_EXTERNAL"
+
+/* *********** LISTS *********** */
+
+/* GPUViewport.storage
+ * Is freed everytime the viewport engine changes */
+typedef struct EXTERNAL_Storage {
+	int dummy;
+} EXTERNAL_Storage;
+
+typedef struct EXTERNAL_StorageList {
+	struct EXTERNAL_Storage *storage;
+	struct EXTERNAL_PrivateData *g_data;
+} EXTERNAL_StorageList;
+
+typedef struct EXTERNAL_FramebufferList {
+	struct GPUFrameBuffer *default_fb;
+} EXTERNAL_FramebufferList;
+
+typedef struct EXTERNAL_TextureList {
+	/* default */
+	struct GPUTexture *depth;
+} EXTERNAL_TextureList;
+
+typedef struct EXTERNAL_PassList {
+	struct DRWPass *depth_pass;
+} EXTERNAL_PassList;
+
+typedef struct EXTERNAL_Data {
+	void *engine_type;
+	EXTERNAL_FramebufferList *fbl;
+	EXTERNAL_TextureList *txl;
+	EXTERNAL_PassList *psl;
+	EXTERNAL_StorageList *stl;
+	char info[GPU_INFO_SIZE];
+} EXTERNAL_Data;
+
+/* *********** STATIC *********** */
+
+static struct {
+	/* Depth Pre Pass */
+	struct GPUShader *depth_sh;
+} e_data = {NULL}; /* Engine data */
+
+typedef struct EXTERNAL_PrivateData {
+	DRWShadingGroup *depth_shgrp;
+} EXTERNAL_PrivateData; /* Transient data */
+
+/* Functions */
+
+static void external_engine_init(void *UNUSED(vedata))
+{
+	/* Depth prepass */
+	if (!e_data.depth_sh) {
+		e_data.depth_sh = DRW_shader_create_3D_depth_only();
+	}
+}
+
+static void external_cache_init(void *vedata)
+{
+	EXTERNAL_PassList *psl = ((EXTERNAL_Data *)vedata)->psl;
+	EXTERNAL_StorageList *stl = ((EXTERNAL_Data *)vedata)->stl;
+
+	if (!stl->g_data) {
+		/* Alloc transient pointers */
+		stl->g_data = MEM_mallocN(sizeof(*stl->g_data), __func__);
+	}
+
+	/* Depth Pass */
+	{
+		psl->depth_pass = DRW_pass_create("Depth Pass", DRW_STATE_WRITE_DEPTH | DRW_STATE_DEPTH_LESS);
+		stl->g_data->depth_shgrp = DRW_shgroup_create(e_data.depth_sh, psl->depth_pass);
+	}
+}
+
+static void external_cache_populate(void *vedata, Object *ob)
+{
+	EXTERNAL_StorageList *stl = ((EXTERNAL_Data *)vedata)->stl;
+
+	if (!DRW_object_is_renderable(ob))
+		return;
+
+	struct Gwn_Batch *geom = DRW_cache_object_surface_get(ob);
+	if (geom) {
+		/* Depth Prepass */
+		DRW_shgroup_call_add(stl->g_data->depth_shgrp, geom, ob->obmat);
+	}
+}
+
+static void external_cache_finish(void *UNUSED(vedata))
+{
+}
+
+static void external_draw_scene_do(void *vedata)
+{
+	const DRWContextState *draw_ctx = DRW_context_state_get();
+	Scene *scene = draw_ctx->scene;
+	RegionView3D *rv3d = draw_ctx->rv3d;
+	ARegion *ar = draw_ctx->ar;
+	RenderEngineType *type;
+
+	DRW_state_reset_ex(DRW_STATE_DEFAULT & ~DRW_STATE_DEPTH_LESS);
+
+	/* Create render engine. */
+	if (!rv3d->render_engine) {
+		RenderEngineType *engine_type = draw_ctx->engine_type;
+
+		if (!(engine_type->view_update && engine_type->render_to_view)) {
+			return;
+		}
+
+		RenderEngine *engine = RE_engine_create_ex(engine_type, true);
+		engine->tile_x = scene->r.tilex;
+		engine->tile_y = scene->r.tiley;
+		engine_type->view_update(engine, draw_ctx->evil_C);
+		rv3d->render_engine = engine;
+	}
+
+	/* Rendered draw. */
+	gpuPushProjectionMatrix();
+	ED_region_pixelspace(ar);
+
+	/* Render result draw. */
+	type = rv3d->render_engine->type;
+	type->render_to_view(rv3d->render_engine, draw_ctx->evil_C);
+
+	gpuPopProjectionMatrix();
+
+	/* Set render info. */
+	EXTERNAL_Data *data = vedata;
+	if (rv3d->render_engine->text[0] != '\0') {
+		BLI_strncpy(data->info, rv3d->render_engine->text, sizeof(data->info));
+	}
+	else {
+		data->info[0] = '\0';
+	}
+}
+
+static void external_draw_scene(void *vedata)
+{
+	const DRWContextState *draw_ctx = DRW_context_state_get();
+	EXTERNAL_PassList *psl = ((EXTERNAL_Data *)vedata)->psl;
+
+	/* Will be NULL during OpenGL render.
+	 * OpenGL render is used for quick preview (thumbnails or sequencer preview)
+	 * where using the rendering engine to preview doesn't make so much sense. */
+	if (draw_ctx->evil_C) {
+		external_draw_scene_do(vedata);
+	}
+	DRW_draw_pass(psl->depth_pass);
+}
+
+static void external_engine_free(void)
+{
+	/* All shaders are builtin. */
+}
+
+static const DrawEngineDataSize external_data_size = DRW_VIEWPORT_DATA_SIZE(EXTERNAL_Data);
+
+DrawEngineType draw_engine_external_type = {
+	NULL, NULL,
+	N_("External"),
+	&external_data_size,
+	&external_engine_init,
+	&external_engine_free,
+	&external_cache_init,
+	&external_cache_populate,
+	&external_cache_finish,
+	NULL,
+	&external_draw_scene,
+	NULL,
+	NULL,
+	NULL,
+};
+
+/* Note: currently unused, we should not register unless we want to see this when debugging the view. */
+
+RenderEngineType DRW_engine_viewport_external_type = {
+	NULL, NULL,
+	EXTERNAL_ENGINE, N_("External"), RE_INTERNAL,
+	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+	&draw_engine_external_type,
+	{NULL, NULL, NULL}
+};
+
+#undef EXTERNAL_ENGINE