From 7a093dc3304b3f306728e1cbdb6f927aeb34e19d Mon Sep 17 00:00:00 2001
From: Matt Gajownik <matt@obsproject.com>
Date: Sat, 28 Jan 2023 18:56:18 +1100
Subject: [PATCH] Render overlay textures in browser sources, such as <select>
 menus

Fixes #148

Reimplements https://github.com/obsproject/obs-browser/commit/3b30eccb6
---
 browser-client.cpp     | 74 ++++++++++++++++++++++++++++++++++++++----
 browser-client.hpp     |  4 +++
 obs-browser-source.cpp | 21 ++++++++++++
 obs-browser-source.hpp |  4 +++
 4 files changed, 97 insertions(+), 6 deletions(-)

diff --git a/browser-client.cpp b/browser-client.cpp
index 1f0e239ef..f540fbe7d 100644
--- a/browser-client.cpp
+++ b/browser-client.cpp
@@ -305,12 +305,43 @@ bool BrowserClient::OnTooltip(CefRefPtr<CefBrowser>, CefString &text)
 #endif
 }
 
+void BrowserClient::OnPopupShow(CefRefPtr<CefBrowser>, bool show)
+{
+	if (!show && !!bs->texture_overlay) {
+		obs_enter_graphics();
+		gs_texture_destroy(bs->texture_overlay);
+		bs->texture_overlay = nullptr;
+		obs_leave_graphics();
+		bs->overlay_x = 0;
+		bs->overlay_y = 0;
+	}
+}
+
+void BrowserClient::OnPopupSize(CefRefPtr<CefBrowser>, const CefRect &rect)
+{
+	if (rect.width > 0) {
+		bs->overlay_x = rect.x;
+		bs->overlay_y = rect.y;
+	}
+}
+
 void BrowserClient::OnPaint(CefRefPtr<CefBrowser>, PaintElementType type,
 			    const RectList &, const void *buffer, int width,
 			    int height)
 {
-	if (type != PET_VIEW) {
-		// TODO Overlay texture on top of bs->texture
+	if (type == PET_POPUP && !!bs->texture && valid()) {
+		obs_enter_graphics();
+		if (bs->texture_overlay) {
+			gs_texture_destroy(bs->texture_overlay);
+			bs->texture_overlay = nullptr;
+		}
+
+		bs->texture_overlay = gs_texture_create(
+			width, height, GS_BGRA, 1, (const uint8_t **)&buffer,
+			GS_DYNAMIC);
+		obs_leave_graphics();
+		return;
+	} else if (type != PET_VIEW) {
 		return;
 	}
 
@@ -385,8 +416,25 @@ void BrowserClient::OnAcceleratedPaint(CefRefPtr<CefBrowser>,
 				       PaintElementType type, const RectList &,
 				       void *shared_handle)
 {
-	if (type != PET_VIEW) {
-		// TODO Overlay texture on top of bs->texture
+	if (type == PET_POPUP && !!bs->texture && valid()) {
+		obs_enter_graphics();
+		if (bs->texture_overlay) {
+			gs_texture_destroy(bs->texture_overlay);
+			bs->texture_overlay = nullptr;
+		}
+#if defined(__APPLE__) && CHROME_VERSION_BUILD > 4183
+		bs->texture_overlay = gs_texture_create_from_iosurface(
+			(IOSurfaceRef)(uintptr_t)shared_handle);
+#elif defined(_WIN32) && CHROME_VERSION_BUILD > 4183
+		bs->texture_overlay = gs_texture_open_nt_shared(
+			(uint32_t)(uintptr_t)shared_handle);
+#else
+		bs->texture_overlay = gs_texture_open_shared(
+			(uint32_t)(uintptr_t)shared_handle);
+#endif
+		obs_leave_graphics();
+		return;
+	} else if (type != PET_VIEW) {
 		return;
 	}
 
@@ -433,8 +481,22 @@ void BrowserClient::OnAcceleratedPaint2(CefRefPtr<CefBrowser>,
 					PaintElementType type, const RectList &,
 					void *shared_handle, bool new_texture)
 {
-	if (type != PET_VIEW) {
-		// TODO Overlay texture on top of bs->texture
+	if (type == PET_POPUP && !!bs->texture && valid()) {
+		obs_enter_graphics();
+		if (bs->texture_overlay) {
+			gs_texture_destroy(bs->texture_overlay);
+			bs->texture_overlay = nullptr;
+		}
+#if defined(_WIN32) && CHROME_VERSION_BUILD > 4183
+		bs->texture_overlay = gs_texture_open_nt_shared(
+			(uint32_t)(uintptr_t)shared_handle);
+#else
+		bs->texture_overlay = gs_texture_open_shared(
+			(uint32_t)(uintptr_t)shared_handle);
+#endif
+		obs_leave_graphics();
+		return;
+	} else if (type != PET_VIEW) {
 		return;
 	}
 
diff --git a/browser-client.hpp b/browser-client.hpp
index ee534e3c8..7cd8043fa 100644
--- a/browser-client.hpp
+++ b/browser-client.hpp
@@ -131,6 +131,10 @@ class BrowserClient : public CefClient,
 	/* CefRenderHandler */
 	virtual void GetViewRect(CefRefPtr<CefBrowser> browser,
 				 CefRect &rect) override;
+	virtual void OnPopupShow(CefRefPtr<CefBrowser> browser,
+				 bool show) override;
+	virtual void OnPopupSize(CefRefPtr<CefBrowser> browser,
+				 const CefRect &rect) override;
 	virtual void OnPaint(CefRefPtr<CefBrowser> browser,
 			     PaintElementType type, const RectList &dirtyRects,
 			     const void *buffer, int width,
diff --git a/obs-browser-source.cpp b/obs-browser-source.cpp
index 82c3d5e0c..bae9dc0c4 100644
--- a/obs-browser-source.cpp
+++ b/obs-browser-source.cpp
@@ -688,6 +688,10 @@ void BrowserSource::Render()
 
 		gs_blend_state_pop();
 
+		// TODO This is washed out on Windows when hardware accelerated
+		while (gs_effect_loop(effect, "Draw"))
+			DrawOverlay(flip);
+
 		gs_enable_framebuffer_srgb(previous);
 	}
 
@@ -699,6 +703,23 @@ void BrowserSource::Render()
 #endif
 }
 
+void BrowserSource::DrawOverlay(bool flip)
+{
+	if (!!texture && !!texture_overlay) {
+		gs_blend_state_push();
+		gs_blend_function_separate(GS_BLEND_SRCALPHA,
+					   GS_BLEND_INVSRCALPHA /*dest_color*/,
+					   GS_BLEND_ONE /*src_alpha*/,
+					   GS_BLEND_INVSRCALPHA /*dest_alpha*/);
+		gs_matrix_push();
+		obs_source_draw(texture_overlay, overlay_x, overlay_y, 0, 0,
+				flip);
+		gs_matrix_pop();
+
+		gs_blend_state_pop();
+	}
+}
+
 static void ExecuteOnBrowser(BrowserFunc func, BrowserSource *bs)
 {
 	lock_guard<mutex> lock(browser_list_mutex);
diff --git a/obs-browser-source.hpp b/obs-browser-source.hpp
index 62e9c570b..8cb05b6df 100644
--- a/obs-browser-source.hpp
+++ b/obs-browser-source.hpp
@@ -67,9 +67,12 @@ struct BrowserSource {
 	std::string url;
 	std::string css;
 	gs_texture_t *texture = nullptr;
+	gs_texture_t *texture_overlay = nullptr;
 	gs_texture_t *extra_texture = nullptr;
 	uint32_t last_cx = 0;
 	uint32_t last_cy = 0;
+	int overlay_x = 0;
+	int overlay_y = 0;
 	gs_color_format last_format = GS_UNKNOWN;
 
 #ifdef ENABLE_BROWSER_SHARED_TEXTURE
@@ -131,6 +134,7 @@ struct BrowserSource {
 	void Update(obs_data_t *settings = nullptr);
 	void Tick();
 	void Render();
+	void DrawOverlay(bool flip);
 #if CHROME_VERSION_BUILD < 4103
 	void ClearAudioStreams();
 	void EnumAudioStreams(obs_source_enum_proc_t cb, void *param);