backend-vnc: GL renderer support

Let the GL renderer render to FBOs and read the pixels into the Neat VNC
frame buffers. This allows to run the VNC backend with the GL renderer.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

libweston/backend-vnc/vnc.c

@@ -55,6 +55,8 @@
 #include <libweston/weston-log.h>
 #include "pixel-formats.h"
 #include "pixman-renderer.h"
+#include "renderer-gl/gl-renderer.h"
+#include "shared/weston-egl-ext.h"
 
 #define DEFAULT_AXIS_STEP_DISTANCE 10
 
@@ -73,6 +75,9 @@ struct vnc_backend {
 	struct wl_event_source *aml_event;
 	struct nvnc *server;
 	int vnc_monitor_refresh_rate;
+
+	const struct pixel_format_info **formats;
+	unsigned int formats_count;
 };
 
 struct vnc_output {
@@ -270,6 +275,11 @@ struct vnc_keysym_to_keycode key_translation[] = {
 	{ },
 };
 
+static const uint32_t vnc_formats[] = {
+	DRM_FORMAT_XRGB8888,
+	DRM_FORMAT_ARGB8888,
+};
+
 static void
 vnc_handle_key_event(struct nvnc_client *client, uint32_t keysym,
 		     bool is_pressed)
@@ -606,18 +616,35 @@ vnc_update_buffer(struct nvnc_display *display, struct pixman_region32 *damage)
 
 	renderbuffer = nvnc_get_userdata(fb);
 	if (!renderbuffer) {
-		const struct pixman_renderer_interface *pixman;
 		const struct pixel_format_info *pfmt;
 
-		pixman = ec->renderer->pixman;
 		pfmt = pixel_format_get_info(DRM_FORMAT_XRGB8888);
 
-		renderbuffer =
-			pixman->create_image_from_ptr(&output->base, pfmt,
-						      output->base.width,
-						      output->base.height,
-						      nvnc_fb_get_addr(fb),
-						      output->base.width * 4);
+		switch (ec->renderer->type) {
+		case WESTON_RENDERER_PIXMAN: {
+			const struct pixman_renderer_interface *pixman;
+
+			pixman = ec->renderer->pixman;
+
+			renderbuffer =
+				pixman->create_image_from_ptr(&output->base, pfmt,
+							      output->base.width,
+							      output->base.height,
+							      nvnc_fb_get_addr(fb),
+							      output->base.width * 4);
+			break;
+		}
+		case WESTON_RENDERER_GL: {
+			renderbuffer =
+				ec->renderer->gl->create_fbo(&output->base, pfmt,
+							     output->base.width,
+							     output->base.height,
+							     nvnc_fb_get_addr(fb));
+			break;
+		}
+		default:
+			unreachable("cannot have auto renderer at runtime");
+		}
 
 		/* This is a new buffer, so the whole surface is damaged. */
 		pixman_region32_copy(&renderbuffer->damage,
@@ -708,13 +735,6 @@ vnc_output_enable(struct weston_output *base)
 	struct vnc_output *output = to_vnc_output(base);
 	struct vnc_backend *backend;
 	struct wl_event_loop *loop;
-	const struct pixman_renderer_output_options options = {
-		.fb_size = {
-			.width = output->base.width,
-			.height = output->base.height,
-		},
-		.format = pixel_format_get_info(DRM_FORMAT_XRGB8888),
-	};
 
 	assert(output);
 
@@ -723,8 +743,37 @@ vnc_output_enable(struct weston_output *base)
 
 	weston_plane_init(&output->cursor_plane, backend->compositor);
 
-	if (renderer->pixman->output_create(&output->base, &options) < 0)
-		return -1;
+	switch (renderer->type) {
+	case WESTON_RENDERER_PIXMAN: {
+		const struct pixman_renderer_output_options options = {
+			.fb_size = {
+				.width = output->base.width,
+				.height = output->base.height,
+			},
+			.format = backend->formats[0],
+		};
+		if (renderer->pixman->output_create(&output->base, &options) < 0)
+			return -1;
+		break;
+	}
+	case WESTON_RENDERER_GL: {
+		const struct gl_renderer_fbo_options options = {
+			.area = {
+				.width = output->base.width,
+				.height = output->base.height,
+			},
+			.fb_size = {
+				.width = output->base.width,
+				.height = output->base.height,
+			},
+		};
+		if (renderer->gl->output_fbo_create(&output->base, &options) < 0)
+			return -1;
+		break;
+	}
+	default:
+		unreachable("cannot have auto renderer at runtime");
+	}
 
 	loop = wl_display_get_event_loop(backend->compositor->wl_display);
 	output->finish_frame_timer = wl_event_loop_add_timer(loop,
@@ -733,7 +782,7 @@ vnc_output_enable(struct weston_output *base)
 
 	output->fb_pool = nvnc_fb_pool_new(output->base.width,
 					   output->base.height,
-					   options.format->format,
+					   backend->formats[0]->format,
 					   output->base.width);
 
 	output->display = nvnc_display_new(0, 0);
@@ -760,7 +809,16 @@ vnc_output_disable(struct weston_output *base)
 	nvnc_display_unref(output->display);
 	nvnc_fb_pool_unref(output->fb_pool);
 
-	renderer->pixman->output_destroy(&output->base);
+	switch (renderer->type) {
+	case WESTON_RENDERER_PIXMAN:
+		renderer->pixman->output_destroy(&output->base);
+		break;
+	case WESTON_RENDERER_GL:
+		renderer->gl->output_destroy(&output->base);
+		break;
+	default:
+		unreachable("cannot have auto renderer at runtime");
+	}
 
 	wl_event_source_remove(output->finish_frame_timer);
 	backend->output = NULL;
@@ -1086,19 +1144,35 @@ vnc_backend_create(struct weston_compositor *compositor,
 	if (weston_compositor_set_presentation_clock_software(compositor) < 0)
 		goto err_compositor;
 
+	backend->formats_count = ARRAY_LENGTH(vnc_formats);
+	backend->formats = pixel_format_get_array(vnc_formats,
+						  backend->formats_count);
+
 	switch (config->renderer) {
 	case WESTON_RENDERER_AUTO:
 	case WESTON_RENDERER_PIXMAN:
+		if (weston_compositor_init_renderer(compositor,
+						    WESTON_RENDERER_PIXMAN,
+						    NULL) < 0)
+			goto err_compositor;
 		break;
+	case WESTON_RENDERER_GL: {
+		const struct gl_renderer_display_options options = {
+			.egl_platform = EGL_PLATFORM_SURFACELESS_MESA,
+			.formats = backend->formats,
+			.formats_count = backend->formats_count,
+		};
+		if (weston_compositor_init_renderer(compositor,
+						    WESTON_RENDERER_GL,
+						    &options.base) < 0)
+			goto err_compositor;
+		break;
+	}
 	default:
 		weston_log("Unsupported renderer requested\n");
 		goto err_compositor;
 	}
 
-	if (weston_compositor_init_renderer(compositor, WESTON_RENDERER_PIXMAN,
-					    NULL) < 0)
-		goto err_compositor;
-
 	vnc_head_create(backend, "vnc");
 
 	compositor->capabilities |= WESTON_CAP_ARBITRARY_MODES;