Get map screenshots working again.

src/display.cpp

@@ -808,10 +808,10 @@ surface display::screenshot(bool map_screenshot)
 	auto clipper = video().set_clip(area);
 
 	map_screenshot_ = true;
-	invalidateAll_ = true;
+	dirty_ = true;
 
 	DBG_DP << "draw() call for map screenshot\n";
-	draw(true, true);
+	draw();
 
 	map_screenshot_ = false;
 
@@ -1655,7 +1655,7 @@ void display::draw_wrap(bool update, bool force)
 		time_between_draws = 1000 / screen_.current_refresh_rate();
 	}
 
-	if(redrawMinimap_) {
+	if(redrawMinimap_ && !map_screenshot_) {
 		redrawMinimap_ = false;
 		draw_minimap();
 	}
@@ -2453,7 +2453,9 @@ void display::draw(bool update, bool force)
 		}
 		drawing_buffer_commit();
 		post_commit();
-		draw_sidebar();
+		if (!map_screenshot_) {
+			draw_sidebar();
+		}
 	}
 	draw_wrap(update, force);
 	post_draw();
@@ -2592,6 +2594,7 @@ void display::draw_hex(const map_location& loc)
 
 	// Paint mouseover overlays
 	if(loc == mouseoverHex_ && (on_map || (in_editor() && get_map().on_board_with_border(loc)))
+			&& !map_screenshot_
 			&& mouseover_hex_overlay_ != nullptr) {
 		// TODO: highdpi - texture, yes this is terrible
 		drawing_buffer_add(LAYER_MOUSEOVER_OVERLAY, loc, dest, texture(mouseover_hex_overlay_));

src/editor/editor_display.cpp

@@ -84,7 +84,7 @@ void editor_display::draw_hex(const map_location& loc)
 	int xpos = get_location_x(loc);
 	int ypos = get_location_y(loc);
 	display::draw_hex(loc);
-	if (map().on_board_with_border(loc)) {
+	if (map().on_board_with_border(loc) && !map_screenshot_) {
 		if (map().in_selection(loc)) {
 			const texture& tex = image::get_texture(
 				"editor/selection-overlay.png", image::TOD_COLORED);

src/game_display.cpp

@@ -268,7 +268,7 @@ void game_display::draw_hex(const map_location& loc)
 		return;
 	}
 
-	if(on_map && loc == mouseoverHex_) {
+	if(on_map && loc == mouseoverHex_ && !map_screenshot_) {
 		drawing_layer hex_top_layer = LAYER_MOUSEOVER_BOTTOM;
 		const unit *u = resources::gameboard->get_visible_unit(loc, dc_->teams()[viewing_team()] );
 		if( u != nullptr ) {

src/video.cpp

@@ -645,7 +645,21 @@ surface CVideo::read_pixels(SDL_Rect* r)
 		WRN_DP << "trying to read pixels with no window" << std::endl;
 		return surface();
 	}
-	SDL_Rect d = draw_area();
+	SDL_Rect d;
+
+	// Get the full target area.
+	SDL_Texture* target = SDL_GetRenderTarget(*window);
+	const bool default_target = !target || target == render_texture_;
+	if (default_target) {
+		d = draw_area();
+	} else {
+		// Assume it's a custom render target.
+		int w, h;
+		SDL_QueryTexture(target, nullptr, nullptr, &w, &h);
+		d = {0, 0, w, h};
+	}
+
+	// Intersect with the given rect.
 	SDL_Rect r_clipped = d;
 	if (r) {
 		r_clipped = sdl::intersect_rects(*r, d);
@@ -656,12 +670,24 @@ surface CVideo::read_pixels(SDL_Rect* r)
 			*r = r_clipped;
 		}
 	}
-	SDL_Rect o = to_output(r_clipped);
+
+	// Convert the rect to output coordinates, if necessary.
+	SDL_Rect o;
+	if (default_target) {
+		o = to_output(r_clipped);
+	} else {
+		// r assumed to already be in output space.
+		o = r_clipped;
+	}
+
+	// Create surface and read pixels
 	surface s(o.w, o.h);
-	// the draw-space viewport may be slightly offset on the render target,
-	// if the scale doesn't match precisely with the window size.
-	o.x += offset_x_;
-	o.y += offset_y_;
+	if (default_target) {
+		// the draw-space viewport may be slightly offset on the render target,
+		// if the scale doesn't match precisely with the window size.
+		o.x += offset_x_;
+		o.y += offset_y_;
+	}
 	SDL_RenderReadPixels(*window, &o, s->format->format, s->pixels, s->pitch);
 	return s;
 }