Eevee: Add Z pass render result.

release/scripts/startup/bl_ui/properties_view_layer.py

@@ -450,6 +450,25 @@ class VIEWLAYER_PT_eevee_indirect_lighting(ViewLayerButtonsPanel, Panel):
         col.template_override_property(layer_props, scene_props, "gi_visibility_resolution")
 
 
+class VIEWLAYER_PT_eevee_layer_passes(ViewLayerButtonsPanel, Panel):
+    bl_label = "Passes"
+    bl_options = {'DEFAULT_CLOSED'}
+    COMPAT_ENGINES = {'BLENDER_EEVEE'}
+
+    def draw(self, context):
+        layout = self.layout
+
+        scene = context.scene
+        rd = scene.render
+        view_layer = scene.view_layers.active
+
+        split = layout.split()
+
+        col = split.column()
+        col.prop(view_layer, "use_pass_combined")
+        col.prop(view_layer, "use_pass_z")
+
+
 classes = (
     VIEWLAYER_UL_viewlayers,
     VIEWLAYER_PT_layers,
@@ -466,6 +485,7 @@ classes = (
     VIEWLAYER_PT_eevee_motion_blur,
     VIEWLAYER_PT_eevee_depth_of_field,
     VIEWLAYER_PT_eevee_bloom,
+    VIEWLAYER_PT_eevee_layer_passes,
 )
 
 if __name__ == "__main__":  # only for live edit.

source/blender/draw/engines/eevee/eevee_render.c

@@ -228,11 +228,19 @@ void EEVEE_render_draw(EEVEE_Data *vedata, struct RenderEngine *UNUSED(engine),
 
 void EEVEE_render_output(EEVEE_Data *vedata, RenderEngine *engine, struct Depsgraph *UNUSED(depsgraph))
 {
+	const DRWContextState *draw_ctx = DRW_context_state_get();
+	ViewLayer *view_layer = draw_ctx->view_layer;
+	DefaultTextureList *dtxl = DRW_viewport_texture_list_get();
+	EEVEE_ViewLayerData *sldata = EEVEE_view_layer_data_ensure();
+	EEVEE_FramebufferList *fbl = vedata->fbl;
 	EEVEE_StorageList *stl = vedata->stl;
+	EEVEE_PrivateData *g_data = stl->g_data;
+	EEVEE_CommonUniformBuffer *common_data = &sldata->common_data;
 
 	const char *viewname = NULL;
 	const float *render_size = DRW_viewport_size_get();
 
+	/* Combined */
 	RenderResult *rr = RE_engine_begin_result(engine, 0, 0, (int)render_size[0], (int)render_size[1], NULL, viewname);
 	RenderLayer *rl = rr->layers.first;
 	RenderPass *rp = RE_pass_find_by_name(rl, RE_PASSNAME_COMBINED, viewname);
@@ -240,5 +248,31 @@ void EEVEE_render_output(EEVEE_Data *vedata, RenderEngine *engine, struct Depsgr
 	DRW_framebuffer_bind(stl->effects->final_fb);
 	DRW_framebuffer_read_data(0, 0, (int)render_size[0], (int)render_size[1], 4, 0, rp->rect);
 
+	if (view_layer->passflag & SCE_PASS_Z) {
+		rp = RE_pass_find_by_name(rl, RE_PASSNAME_Z, viewname);
+
+		DRW_framebuffer_texture_attach(fbl->main, dtxl->depth, 0, 0);
+		DRW_framebuffer_bind(fbl->main);
+		DRW_framebuffer_read_depth(0, 0, (int)render_size[0], (int)render_size[1], rp->rect);
+
+		bool is_persp = DRW_viewport_is_persp_get();
+
+		/* Convert ogl depth [0..1] to view Z [near..far] */
+		for (int i = 0; i < (int)render_size[0] * (int)render_size[1]; ++i) {
+			if (rp->rect[i] == 1.0f ) {
+				rp->rect[i] = 1e10f; /* Background */
+			}
+			else {
+				if (is_persp) {
+					rp->rect[i] = rp->rect[i] * 2.0f - 1.0f;
+					rp->rect[i] = g_data->winmat[3][2] / (rp->rect[i] + g_data->winmat[2][2]);
+				}
+				else {
+					rp->rect[i] = -common_data->view_vecs[0][2] + rp->rect[i] * -common_data->view_vecs[1][2];
+				}
+			}
+		}
+	}
+
 	RE_engine_end_result(engine, rr, false, false, false);
 }

source/blender/draw/intern/DRW_render.h

@@ -238,6 +238,7 @@ void DRW_framebuffer_init(
 void DRW_framebuffer_bind(struct GPUFrameBuffer *fb);
 void DRW_framebuffer_clear(bool color, bool depth, bool stencil, float clear_col[4], float clear_depth);
 void DRW_framebuffer_read_data(int x, int y, int w, int h, int channels, int slot, float *data);
+void DRW_framebuffer_read_depth(int x, int y, int w, int h, float *data);
 void DRW_framebuffer_texture_attach(struct GPUFrameBuffer *fb, struct GPUTexture *tex, int slot, int mip);
 void DRW_framebuffer_texture_layer_attach(struct GPUFrameBuffer *fb, struct GPUTexture *tex, int slot, int layer, int mip);
 void DRW_framebuffer_cubeface_attach(struct GPUFrameBuffer *fb, struct GPUTexture *tex, int slot, int face, int mip);

source/blender/draw/intern/draw_manager.c

@@ -2415,6 +2415,14 @@ void DRW_framebuffer_read_data(int x, int y, int w, int h, int channels, int slo
 	glReadPixels(x, y, w, h, type, GL_FLOAT, data);
 }
 
+void DRW_framebuffer_read_depth(int x, int y, int w, int h, float *data)
+{
+	GLenum type = GL_DEPTH_COMPONENT;
+
+	glReadBuffer(GL_COLOR_ATTACHMENT0); /* This is OK! */
+	glReadPixels(x, y, w, h, type, GL_FLOAT, data);
+}
+
 void DRW_framebuffer_texture_attach(struct GPUFrameBuffer *fb, GPUTexture *tex, int slot, int mip)
 {
 	GPU_framebuffer_texture_attach(fb, tex, slot, mip);