win-capture: Support linear SRGB

For game capture, neither GL nor D3D9 support SRGB shared textures, so
disable linear SRGB support if the texture format doesn't support it.

Similarly, DXGI display capture doesn't work with SRGB at the moment.
Unsure if it will with more work, but disable for now.

Also force linear SRGB off if using GDI-compatible textures.

plugins/win-capture/dc-capture.c

@@ -172,7 +172,15 @@ static void draw_texture(struct dc_capture *capture, gs_effect_t *effect)
 	gs_eparam_t *image = gs_effect_get_param_by_name(effect, "image");
 	size_t passes;
 
-	gs_effect_set_texture(image, texture);
+	const bool linear_srgb = gs_get_linear_srgb() && capture->compatibility;
+
+	const bool previous = gs_framebuffer_srgb_enabled();
+	gs_enable_framebuffer_srgb(linear_srgb);
+
+	if (linear_srgb)
+		gs_effect_set_texture_srgb(image, texture);
+	else
+		gs_effect_set_texture(image, texture);
 
 	passes = gs_technique_begin(tech);
 	for (size_t i = 0; i < passes; i++) {
@@ -186,6 +194,8 @@ static void draw_texture(struct dc_capture *capture, gs_effect_t *effect)
 		}
 	}
 	gs_technique_end(tech);
+
+	gs_enable_framebuffer_srgb(previous);
 }
 
 void dc_capture_render(struct dc_capture *capture, gs_effect_t *effect)

plugins/win-capture/duplicator-monitor-capture.c

@@ -236,6 +236,8 @@ static void duplicator_capture_render(void *data, gs_effect_t *effect)
 
 	rot = capture->rot;
 
+	const bool previous = gs_set_linear_srgb(false);
+
 	while (gs_effect_loop(effect, "Draw")) {
 		if (rot != 0) {
 			float x = 0.0f;
@@ -265,6 +267,8 @@ static void duplicator_capture_render(void *data, gs_effect_t *effect)
 			gs_matrix_pop();
 	}
 
+	gs_set_linear_srgb(previous);
+
 	if (capture->capture_cursor) {
 		effect = obs_get_base_effect(OBS_EFFECT_DEFAULT);
 

plugins/win-capture/game-capture.c

@@ -149,6 +149,7 @@ struct game_capture {
 
 	ipc_pipe_server_t pipe;
 	gs_texture_t *texture;
+	bool supports_srgb;
 	struct hook_info *global_hook_info;
 	HANDLE keepalive_mutex;
 	HANDLE hook_init;
@@ -1574,6 +1575,7 @@ static inline bool init_shmem_capture(struct game_capture *gc)
 		return false;
 	}
 
+	gc->supports_srgb = true;
 	gc->copy_texture = copy_shmem_tex;
 	return true;
 }
@@ -1583,6 +1585,8 @@ static inline bool init_shtex_capture(struct game_capture *gc)
 	obs_enter_graphics();
 	gs_texture_destroy(gc->texture);
 	gc->texture = gs_texture_open_shared(gc->shtex_data->tex_handle);
+	enum gs_color_format format = gs_texture_get_color_format(gc->texture);
+	gc->supports_srgb = gs_is_srgb_format(format);
 	obs_leave_graphics();
 
 	if (!gc->texture) {
@@ -1808,6 +1812,9 @@ static void game_capture_render(void *data, gs_effect_t *effect)
 					     ? OBS_EFFECT_DEFAULT
 					     : OBS_EFFECT_OPAQUE);
 
+	const bool linear_srgb = gs_get_linear_srgb() && gc->supports_srgb;
+	const bool previous = gs_set_linear_srgb(linear_srgb);
+
 	while (gs_effect_loop(effect, "Draw")) {
 		obs_source_draw(gc->texture, 0, 0, 0, 0,
 				gc->global_hook_info->flip);
@@ -1818,6 +1825,8 @@ static void game_capture_render(void *data, gs_effect_t *effect)
 		}
 	}
 
+	gs_set_linear_srgb(previous);
+
 	if (!gc->config.allow_transparency && gc->config.cursor &&
 	    !gc->cursor_hidden) {
 		effect = obs_get_base_effect(OBS_EFFECT_DEFAULT);