Render: add "OpenGL" render engine.

This is intended for quick renders for previsualization, animation previews
or sequencer previews. It provides the same settings as found in the 3D view
Shading popover in solid display mode, but in the scene render properties.

The "Workbench" engine was removed, and this name no longer appears in the
user interface, it's purely an internal name. We might come up with a better
name for this OpenGL engine still, but it's good to be consistent with the
OpenGL Render operator name since this has a similar purpose.

4 files changed, 33 insertions, 2 deletions

diff --git a/source/blender/blenkernel/BKE_scene.h b/source/blender/blenkernel/BKE_scene.h
index 270ab60c02b..adccfda8e25 100644
--- a/source/blender/blenkernel/BKE_scene.h
+++ b/source/blender/blenkernel/BKE_scene.h
@@ -156,6 +156,7 @@ bool BKE_scene_use_shading_nodes_custom(struct Scene *scene);
 bool BKE_scene_use_spherical_stereo(struct Scene *scene);
 
 bool BKE_scene_uses_blender_eevee(const struct Scene *scene);
+bool BKE_scene_uses_blender_opengl(const struct Scene *scene);
 bool BKE_scene_uses_cycles(const struct Scene *scene);
 
 void BKE_scene_disable_color_management(struct Scene *scene);
diff --git a/source/blender/blenkernel/BKE_screen.h b/source/blender/blenkernel/BKE_screen.h
index 60981c6e76e..c74170becb4 100644
--- a/source/blender/blenkernel/BKE_screen.h
+++ b/source/blender/blenkernel/BKE_screen.h
@@ -45,6 +45,7 @@ struct ScrVert;
 struct SpaceType;
 struct TransformOrientation;
 struct View3D;
+struct View3DShading;
 struct bContext;
 struct bContextDataResult;
 struct bScreen;
@@ -355,6 +356,8 @@ bool BKE_screen_is_used(const struct bScreen *screen) ATTR_WARN_UNUSED_RESULT AT
 float BKE_screen_view3d_zoom_to_fac(float camzoom);
 float BKE_screen_view3d_zoom_from_fac(float zoomfac);
 
+void BKE_screen_view3d_shading_init(struct View3DShading *shading);
+
 /* screen */
 void BKE_screen_free(struct bScreen *sc);
 void BKE_screen_area_map_free(struct ScrAreaMap *area_map) ATTR_NONNULL();
diff --git a/source/blender/blenkernel/intern/scene.c b/source/blender/blenkernel/intern/scene.c
index 3b1416d2881..f99a30b75d0 100644
--- a/source/blender/blenkernel/intern/scene.c
+++ b/source/blender/blenkernel/intern/scene.c
@@ -113,7 +113,7 @@
 #include "bmesh.h"
 
 const char *RE_engine_id_BLENDER_EEVEE = "BLENDER_EEVEE";
-const char *RE_engine_id_BLENDER_WORKBENCH = "BLENDER_WORKBENCH";
+const char *RE_engine_id_BLENDER_OPENGL = "BLENDER_OPENGL";
 const char *RE_engine_id_CYCLES = "CYCLES";
 
 void free_avicodecdata(AviCodecData *acd)
@@ -361,6 +361,9 @@ Scene *BKE_scene_copy(Main *bmain, Scene *sce, int type)
 
 		curvemapping_copy_data(&sce_copy->r.mblur_shutter_curve, &sce->r.mblur_shutter_curve);
 
+		/* viewport display settings */
+		sce_copy->display = sce->display;
+
 		/* tool settings */
 		sce_copy->toolsettings = BKE_toolsettings_copy(sce->toolsettings, 0);
 
@@ -820,6 +823,9 @@ void BKE_scene_init(Scene *sce)
 	sce->display.matcap_ssao_attenuation = 1.0f;
 	sce->display.matcap_ssao_samples = 16;
 
+	/* OpenGL Render. */
+	BKE_screen_view3d_shading_init(&sce->display.shading);
+
 	/* SceneEEVEE */
 	sce->eevee.gi_diffuse_bounces = 3;
 	sce->eevee.gi_cubemap_resolution = 512;
@@ -1541,6 +1547,11 @@ bool BKE_scene_uses_blender_eevee(const Scene *scene)
 	return STREQ(scene->r.engine, RE_engine_id_BLENDER_EEVEE);
 }
 
+bool BKE_scene_uses_blender_opengl(const Scene *scene)
+{
+	return STREQ(scene->r.engine, RE_engine_id_BLENDER_OPENGL);
+}
+
 bool BKE_scene_uses_cycles(const Scene *scene)
 {
 	return STREQ(scene->r.engine, RE_engine_id_CYCLES);
diff --git a/source/blender/blenkernel/intern/screen.c b/source/blender/blenkernel/intern/screen.c
index 448b97c63b3..f8d926a13ed 100644
--- a/source/blender/blenkernel/intern/screen.c
+++ b/source/blender/blenkernel/intern/screen.c
@@ -45,9 +45,10 @@
 #include "DNA_view3d_types.h"
 #include "DNA_workspace_types.h"
 
+#include "BLI_math_vector.h"
 #include "BLI_listbase.h"
-#include "BLI_utildefines.h"
 #include "BLI_rect.h"
+#include "BLI_utildefines.h"
 
 #include "BKE_icons.h"
 #include "BKE_idprop.h"
@@ -855,6 +856,21 @@ void BKE_screen_view3d_scene_sync(bScreen *sc, Scene *scene)
 	}
 }
 
+void BKE_screen_view3d_shading_init(View3DShading *shading)
+{
+	memset(shading, 0, sizeof(*shading));
+
+	shading->type = OB_SOLID;
+	shading->prev_type = OB_SOLID;
+	shading->flag = V3D_SHADING_SPECULAR_HIGHLIGHT;
+	shading->light = V3D_LIGHTING_STUDIO;
+	shading->shadow_intensity = 0.5f;
+	shading->xray_alpha = 0.5f;
+	shading->cavity_valley_factor = 1.0f;
+	shading->cavity_ridge_factor = 1.0f;
+	copy_v3_fl(shading->single_color, 0.8f);
+}
+
 /* magic zoom calculation, no idea what
  * it signifies, if you find out, tell me! -zr
  */