Toggle 3DS lower screen backlight by touching screen (#190)

src/platform/3ds/main.cpp

@@ -37,6 +37,9 @@ bool osJoyReady(int index) {
     return index == 0;
 }
 
+// backlight
+bool bottomScreenOn = true;
+
 void osJoyVibrate(int index, float L, float R) {
     //
 }
@@ -67,6 +70,18 @@ void inputUpdate() {
 
     if (fabsf(stickL.x) < 0.3f && fabsf(stickL.y) < 0.3f) stickL = vec2(0.0f);
     Input::setJoyPos(0, jkL, stickL);
+
+    if (hidKeysDown() & KEY_TOUCH) {
+        gspLcdInit();
+        if (bottomScreenOn) {
+            GSPLCD_PowerOffBacklight(GSPLCD_SCREEN_BOTTOM);
+            bottomScreenOn = false;
+        } else {
+            GSPLCD_PowerOnBacklight(GSPLCD_SCREEN_BOTTOM);
+            bottomScreenOn = true;
+        }
+        gspLcdExit();
+    }
 }
 
 void inputFree() {
@@ -181,6 +196,11 @@ int main() {
 
     inputFree();
     sndFree();
+    if (!bottomScreenOn) {
+        gspLcdInit();
+        GSPLCD_PowerOnBacklight(GSPLCD_SCREEN_BOTTOM);
+        gspLcdExit();
+    }
     Game::deinit();
 
     return 0;