UPBGE: Implement render extra attachment. (#774)

In the purpose of complex filters, data from the rendering other than the final
color or the depth could be needed in filter like space reflection or ambient
occlusion. The obvious one is the view normal, but any kind of data could be
interesting passing from the albedo or diffuse to a debug color for screen ray
cast.
To expose such feature to the user, first a list of attachments need to be
defined and secondly a way to output to these from simple material or node
material.

The attachments are to the number of 7, because the 8th is the first one
dedicated to the final color. The UI is defined in "Render" panel under
"Attachments" sub panel. A list of 7 items is exposed and the user can add an
attachment or remove one from any item, the items have four properties, the name
(only for debug), the type : either custom, normal or albedo, in case of custom
the properties size and hdr are exposed, they both select the size of data into
the attachment texture and it's precision type.

Each GPU material is now tracking 8 out links, the first one is the same as the
previous only out link and the other match the extra attachment. They are all
iterated in codegen_call_functions to generate the GLSL lines for
"gl_FragData[i] = ", a out link is registered using the function
GPU_material_output_link.

The attachment type "custom" is dedicated only for node materials where any kind
of data could be output to a special node. This node is named "Output
Attachment" and has only one input and a property for the index of the
attachment, this node is responsible of registering the output link.
The other attachment types "normal" and "abeldo" are detected in
GPU_shaderesult_set and generate link for the view normal and the material
diffuse (including vertex color and textures) multiplied by the object color.

From the game engine side, the attachment info are converted into LA_Launcher
and put inside RAS_ICanvas, this same class is now responsible of owning and
creating the offscreens, by doing this the canvas can also detect properly a
resize and recreate the offscreens. Other than that the function are equivalent,
GetOffScreen is now called from RAS_ICanvas instead of RAS_Rasterizer.

The attachments are readable form any filters defining the sampler uniform
"bgl_DataTextures[7]", this uniform is bind as well as other uniforms in
RAS_2DFilter::BindUniforms and the attachments textures in
BindTextures/UnbindTextures.

Because GPUOffScreen is not anymore used and is less flexible than hand
configuration of a frame buffer, their sources are restored to the blender ones.

Author: panzergame

release/scripts/startup/bl_ui/properties_game.py

@@ -18,7 +18,7 @@
 
 # <pep8 compliant>
 import bpy
-from bpy.types import Panel, Menu
+from bpy.types import Panel, Menu, UIList
 
 
 class PhysicsButtonsPanel:
@@ -462,6 +462,42 @@ def draw(self, context):
         col.label("Exit Key:")
         col.prop(gs, "exit_key", text="", event=True)
 
+class RENDER_UL_attachments(UIList):
+    def draw_item(self, context, layout, data, item, icon, active_data, active_propname, index):
+        if item is not None:
+            layout.prop(item, "name", text="", emboss=False, icon="TEXTURE")
+            layout.label(text=str(index))
+        else:
+            layout.label(text="", icon="TEXTURE")
+
+class RENDER_PT_game_attachments(RenderButtonsPanel, Panel):
+    bl_label = "Attachments"
+    COMPAT_ENGINES = {'BLENDER_GAME'}
+
+    def draw(self, context):
+        layout = self.layout
+
+        gs = context.scene.game_settings
+
+        row = layout.row()
+
+        row.template_list("RENDER_UL_attachments", "", gs, "attachment_slots", gs, "active_attachment_index", rows=2)
+
+        col = row.column(align=True)
+        col.operator("scene.render_attachment_new", icon='ZOOMIN', text="")
+        col.operator("scene.render_attachment_remove", icon='ZOOMOUT', text="")
+
+        attachment = gs.active_attachment
+
+        if attachment is not None:
+            row = layout.row()
+            row.prop(attachment, "type")
+            row.prop(attachment, "hdr")
+
+            if attachment.type == "CUSTOM":
+                row = layout.row()
+                row.prop(attachment, "size")
+
 
 class RENDER_PT_game_animations(RenderButtonsPanel, Panel):
     bl_label = "Animations"
@@ -1061,10 +1097,12 @@ def draw(self, context):
     RENDER_PT_game_stereo,
     RENDER_PT_game_shading,
     RENDER_PT_game_system,
+    RENDER_PT_game_attachments,
     RENDER_PT_game_animations,
     RENDER_PT_game_display,
     RENDER_PT_game_color_management,
     RENDER_PT_game_debug,
+	RENDER_UL_attachments,
     SCENE_PT_game_physics,
     SCENE_PT_game_physics_obstacles,
     SCENE_PT_game_navmesh,

release/scripts/startup/nodeitems_builtins.py

@@ -165,6 +165,7 @@ def object_shader_nodes_poll(context):
     ]),
     ShaderOldNodeCategory("SH_OUTPUT", "Output", items=[
         NodeItem("ShaderNodeOutput"),
+        NodeItem("ShaderNodeOutputAttachment"),
         NodeItem("NodeGroupOutput", poll=group_input_output_item_poll),
     ]),
     ShaderOldNodeCategory("SH_OP_COLOR", "Color", items=[

source/blender/blenkernel/BKE_node.h

@@ -800,6 +800,7 @@ struct ShadeResult;
 #define SH_NODE_OBJECT			1000
 #define SH_NODE_TIME			1001
 #define SH_NODE_PARALLAX		1002
+#define SH_NODE_OUTPUT_ATTACHMENT 1003
 
 /* custom defines options for Material node */
 #define SH_NODE_MAT_DIFF   1

source/blender/blenkernel/intern/node.c

@@ -1879,7 +1879,7 @@ void ntreeSetOutput(bNodeTree *ntree)
 			int output = 0;
 
 			/* we need a check for which output node should be tagged like this, below an exception */
-			if (node->type == CMP_NODE_OUTPUT_FILE)
+			if (ELEM(node->type, CMP_NODE_OUTPUT_FILE, SH_NODE_OUTPUT_ATTACHMENT))
 				continue;
 
 			/* there is more types having output class, each one is checked */
@@ -3637,6 +3637,7 @@ static void registerShaderNodes(void)
 	register_node_type_sh_uvmap();
 	register_node_type_sh_uvalongstroke();
 
+	register_node_type_sh_output_attachment();
 	register_node_type_sh_output_lamp();
 	register_node_type_sh_output_material();
 	register_node_type_sh_output_world();

source/blender/blenkernel/intern/scene.c

@@ -518,6 +518,12 @@ void BKE_scene_free(Scene *sce)
 
 	BKE_previewimg_free(&sce->preview);
 	curvemapping_free_data(&sce->r.mblur_shutter_curve);
+
+	for (unsigned short i = 0; i < GAME_ATTACHMENT_COUNT; ++i) {
+		if (sce->gm.attachments[i]) {
+			MEM_freeN(sce->gm.attachments[i]);
+		}
+	}
 }
 
 void BKE_scene_init(Scene *sce)

source/blender/blenloader/intern/readfile.c

@@ -6305,6 +6305,10 @@ static void direct_link_scene(FileData *fd, Scene *sce)
 	sce->preview = direct_link_preview_image(fd, sce->preview);
 
 	direct_link_curvemapping(fd, &sce->r.mblur_shutter_curve);
+
+	for (unsigned short a = 0; a < GAME_ATTACHMENT_COUNT; a++) {
+		sce->gm.attachments[a] = newdataadr(fd, sce->gm.attachments[a]);
+	}
 }
 
 /* ************ READ WM ***************** */

source/blender/blenloader/intern/writefile.c

@@ -2735,6 +2735,12 @@ static void write_scene(WriteData *wd, Scene *sce)
 
 	write_previews(wd, sce->preview);
 	write_curvemapping_curves(wd, &sce->r.mblur_shutter_curve);
+
+	for (unsigned short a = 0; a < GAME_ATTACHMENT_COUNT; a++) {
+		if (sce->gm.attachments[a]) {
+			writestruct(wd, DATA, RenderAttachment, 1, sce->gm.attachments[a]);
+		}
+	}
 }
 
 static void write_gpencil(WriteData *wd, bGPdata *gpd)

source/blender/editors/render/render_intern.h

@@ -59,6 +59,9 @@ void SCENE_OT_render_layer_remove(struct wmOperatorType *ot);
 void SCENE_OT_render_view_add(struct wmOperatorType *ot);
 void SCENE_OT_render_view_remove(struct wmOperatorType *ot);
 
+void SCENE_OT_render_attachment_new(struct wmOperatorType *ot);
+void SCENE_OT_render_attachment_remove(struct wmOperatorType *ot);
+
 #ifdef WITH_FREESTYLE
 void SCENE_OT_freestyle_module_add(struct wmOperatorType *ot);
 void SCENE_OT_freestyle_module_remove(struct wmOperatorType *ot);

source/blender/editors/render/render_opengl.c

@@ -634,7 +634,7 @@ static bool screen_opengl_render_init(bContext *C, wmOperator *op)
 	sizey = (scene->r.size * scene->r.ysch) / 100;
 
 	/* corrects render size with actual size, not every card supports non-power-of-two dimensions */
-	ofs = GPU_offscreen_create(sizex, sizey, full_samples ? 0 : samples, GPU_HDR_NONE, GPU_OFFSCREEN_DEPTH_COMPARE, err_out);
+	ofs = GPU_offscreen_create(sizex, sizey, full_samples ? 0 : samples, err_out);
 
 	if (!ofs) {
 		BKE_reportf(op->reports, RPT_ERROR, "Failed to create OpenGL off-screen buffer, %s", err_out);

source/blender/editors/render/render_ops.c

@@ -62,6 +62,9 @@ void ED_operatortypes_render(void)
 	WM_operatortype_append(SCENE_OT_render_view_add);
 	WM_operatortype_append(SCENE_OT_render_view_remove);
 
+	WM_operatortype_append(SCENE_OT_render_attachment_new);
+	WM_operatortype_append(SCENE_OT_render_attachment_remove);
+
 #ifdef WITH_FREESTYLE
 	WM_operatortype_append(SCENE_OT_freestyle_module_add);
 	WM_operatortype_append(SCENE_OT_freestyle_module_remove);