examples: add render-pass-ext exmaple

examples/render-pass-ext/triangle_pass.c

@@ -0,0 +1,95 @@
+#include <assert.h>
+#include <wlr/config.h>
+#include <wlr/render/pixman.h>
+#include <wlr/render/pass.h>
+#if WLR_HAS_GLES2_RENDERER
+#include <wlr/render/gles2.h>
+#endif
+#if WLR_HAS_VULKAN_RENDERER
+#include <wlr/render/vulkan.h>
+#endif
+#include <wlr/render/interface.h>
+#include <wlr/util/log.h>
+
+#include "triangle_pass.h"
+#include "pixman/triangle_pass.h"
+#if WLR_HAS_GLES2_RENDERER
+#include "gles2/triangle_pass.h"
+#endif
+
+void render_triangle_pass_init(struct render_triangle_pass *pass,
+		const struct render_triangle_pass_impl *impl) {
+	assert(impl->render);
+	*pass = (struct render_triangle_pass){
+		.impl = impl,
+	};
+
+	wl_signal_init(&pass->events.destroy);
+}
+
+void render_triangle_pass_destroy(struct render_triangle_pass *pass) {
+	if (pass == NULL) {
+		return;
+	}
+
+	pass->impl->destroy(pass);
+}
+
+struct render_triangle_pass *get_or_create_render_triangle_pass(
+		struct wlr_renderer *renderer) {
+	if (renderer == NULL) {
+		return NULL;
+	}
+
+	if (renderer->data == NULL) {
+		struct render_triangle_pass *pass = NULL;
+		if (wlr_renderer_is_pixman(renderer)) {
+			pass = pixman_render_triangle_pass_create(renderer);
+		}
+
+#if WLR_HAS_GLES2_RENDERER
+		else if (wlr_renderer_is_gles2(renderer)) {
+			pass = gles2_render_triangle_pass_create(renderer);
+		}
+#endif
+
+// #if WLR_HAS_VULKAN_RENDERER
+// 		else if (wlr_renderer_is_vk(renderer)) {
+// 			pass = wlr_vk_render_triangle_pass_create(renderer);
+// 		}
+// #endif
+
+		renderer->data = pass;
+		return pass;
+	} else {
+		return renderer->data;
+	}
+}
+
+void render_triangle_pass_add(struct wlr_render_pass *render_pass,
+	const struct custom_render_triangle_options *options) {
+	struct wlr_renderer *renderer =
+		wlr_get_wlr_renderer_from_render_pass(render_pass);
+
+	struct render_triangle_pass *pass = renderer->data;
+	if (pass == NULL) {
+		wlr_log(WLR_ERROR, "No triangle pass is available for this renderer");
+		return;
+	}
+	return pass->impl->render(render_pass, options);
+}
+
+void custom_render_triangle_options_get_box(const struct custom_render_triangle_options *options,
+		const struct wlr_buffer *buffer, struct wlr_box *box) {
+	if (wlr_box_empty(&options->box)) {
+		*box = (struct wlr_box){
+			.width = buffer->width,
+			.height = buffer->height,
+		};
+
+		return;
+	}
+
+	*box = options->box;
+}
+