+static void SetGadgetPosition_OverlayTouchButton(struct GadgetInfo *gi)
+{
+ gi->x = gi->orig_x;
+ gi->y = gi->orig_y;
+
+ if (gi->x < 0)
+ gi->x += video.screen_width;
+ if (gi->y < 0)
+ gi->y += video.screen_height;
+
+ gi->x -= video.screen_xoffset;
+ gi->y -= video.screen_yoffset;
+}
+
+void SetGadgetsPosition_OverlayTouchButtons(void)
+{
+ struct GadgetInfo *gi;
+
+ if (gadget_list_first_entry == NULL)
+ return;
+
+ for (gi = gadget_list_first_entry; gi != NULL; gi = gi->next)
+ if (gi->overlay_touch_button)
+ SetGadgetPosition_OverlayTouchButton(gi);
+}
+
+static void DrawGadget_OverlayTouchButton(struct GadgetInfo *gi)
+{
+ struct GadgetDesign *gd;
+ int state = (gi->state ? GD_BUTTON_PRESSED : GD_BUTTON_UNPRESSED);
+
+ if (gi == NULL || gi->deactivated)
+ return;
+
+ gd = (!gi->active ? &gi->alt_design[state] :
+ gi->checked ? &gi->alt_design[state] : &gi->design[state]);
+
+ int x = gi->x + video.screen_xoffset;
+ int y = gi->y + video.screen_yoffset;
+ int alpha = gi->overlay_touch_button_alpha;
+ int alpha_max = SDL_ALPHA_OPAQUE;
+ int alpha_step = ALPHA_FADING_STEPSIZE(alpha_max);
+
+ // only show mapped overlay touch buttons if touch screen is really used
+ if (gi->mapped && runtime.uses_touch_device)
+ {
+ if (alpha < alpha_max)
+ alpha = MIN(alpha + alpha_step, alpha_max);
+ }
+ else
+ {
+ alpha = MAX(0, alpha - alpha_step);
+ }
+
+ gi->overlay_touch_button_alpha = alpha;
+
+ if (alpha == 0)
+ return;
+
+ switch (gi->type)
+ {
+ case GD_TYPE_NORMAL_BUTTON:
+ case GD_TYPE_CHECK_BUTTON:
+ case GD_TYPE_RADIO_BUTTON:
+ SDL_SetTextureAlphaMod(gd->bitmap->texture_masked, alpha);
+ SDL_SetTextureBlendMode(gd->bitmap->texture_masked, SDL_BLENDMODE_BLEND);
+
+ BlitToScreenMasked(gd->bitmap, gd->x, gd->y, gi->width, gi->height, x, y);
+ break;
+
+ default:
+ return;
+ }
+}
+
+void DrawGadgets_OverlayTouchButtons(void)
+{
+ struct GadgetInfo *gi;
+
+ if (gadget_list_first_entry == NULL)
+ return;
+
+ for (gi = gadget_list_first_entry; gi != NULL; gi = gi->next)
+ if (gi->overlay_touch_button)
+ DrawGadget_OverlayTouchButton(gi);
+}
+
+boolean CheckPosition_OverlayTouchButtons(int mx, int my, int button)
+{
+ struct GadgetInfo *gi = getGadgetInfoFromMousePosition(mx, my, button);
+
+ return (gi != NULL && gi->overlay_touch_button);
+}
+