[rcore] Fix `IsMouseButtonUp()` and add touch events for `PLATFORM_DESKTOP_SDL` (#3610)

* Fix IsMouseButtonUp() and add touch events for PLATFORM_DESKTOP_SDL

* Fix coding convention

src/platforms/rcore_desktop_sdl.c

@@ -1138,6 +1138,7 @@ void PollInputEvents(void)
                 else if (btn == 1) btn = 2;
 
                 CORE.Input.Mouse.currentButtonState[btn] = 1;
+                CORE.Input.Touch.currentTouchState[btn] = 1;
 
                 touchAction = 1;
                 gestureUpdate = true;
@@ -1151,6 +1152,7 @@ void PollInputEvents(void)
                 else if (btn == 1) btn = 2;
 
                 CORE.Input.Mouse.currentButtonState[btn] = 0;
+                CORE.Input.Touch.currentTouchState[btn] = 0;
 
                 touchAction = 0;
                 gestureUpdate = true;
@@ -1179,6 +1181,31 @@ void PollInputEvents(void)
                 gestureUpdate = true;
             } break;
 
+            // Check touch events
+            // NOTE: These cases need to be reviewed on a real touch screen
+            case SDL_FINGERDOWN:
+            {
+                CORE.Input.Touch.currentTouchState[event.tfinger.fingerId] = 1;
+
+                touchAction = 1;
+                gestureUpdate = true;
+            } break;
+            case SDL_FINGERUP:
+            {
+                CORE.Input.Touch.currentTouchState[event.tfinger.fingerId] = 0;
+
+                touchAction = 0;
+                gestureUpdate = true;
+            } break;
+            case SDL_FINGERMOTION:
+            {
+                CORE.Input.Touch.position[event.tfinger.fingerId].x = (float)event.motion.x;
+                CORE.Input.Touch.position[event.tfinger.fingerId].y = (float)event.motion.y;
+
+                touchAction = 2;
+                gestureUpdate = true;
+            } break;
+
             // Check gamepad events
             case SDL_JOYAXISMOTION:
             {