switch: add touchscreen support

src/video/switch/SDL_switchtouch.c

@@ -0,0 +1,115 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2017 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "../../SDL_internal.h"
+
+#if SDL_VIDEO_DRIVER_SWITCH
+
+#include <switch.h>
+
+#include "SDL_events.h"
+#include "SDL_switchtouch.h"
+#include "../../events/SDL_touch_c.h"
+
+#define MAX_TOUCH 16
+
+typedef struct SwitchTouch
+{
+    SDL_FingerID id;
+    touchPosition position;
+} SwitchTouch;
+
+typedef struct TouchState
+{
+    SwitchTouch touch[MAX_TOUCH];
+    u32 count;
+} TouchState;
+
+TouchState touchState;
+
+TouchState touchState_old;
+
+void
+SWITCH_InitTouch(void)
+{
+    SDL_AddTouch((SDL_TouchID) 0, "Switch");
+}
+
+void
+SWITCH_QuitTouch(void)
+{
+
+}
+
+void
+SWITCH_PollTouch(void)
+{
+    memcpy(&touchState_old, &touchState, sizeof(touchState));
+
+    touchState.count = hidTouchCount();
+    if (touchState.count >= MAX_TOUCH) {
+        touchState.count = MAX_TOUCH - 1;
+    }
+
+    if (touchState.count > 0) {
+        for (u32 i = 0; i < touchState.count; i++) {
+
+            touchState.touch[i].id = i;
+            hidTouchRead(&touchState.touch[i].position, i);
+
+            // Send an initial touch
+            SDL_SendTouch(0, (SDL_FingerID) i, SDL_TRUE,
+                          (float) touchState.touch[i].position.px / 1280.0f,
+                          (float) touchState.touch[i].position.py / 720.0f, 1);
+
+            // Always send the motion
+            SDL_SendTouchMotion(0, (SDL_FingerID) i,
+                                (float) touchState.touch[i].position.px / 1280.0f,
+                                (float) touchState.touch[i].position.py / 720.0f, 1);
+        }
+    }
+
+    // some fingers might have been let go
+    if (touchState_old.count > 0) {
+
+        for (int i = 0; i < touchState_old.count; i++) {
+
+            int finger_up = 1;
+            if (touchState.count > 0) {
+                for (int j = 0; j < touchState.count; j++) {
+                    if (touchState.touch[j].id == touchState_old.touch[i].id) {
+                        finger_up = 0;
+                    }
+                }
+            }
+
+            if (finger_up == 1) {
+                // Finger released from screen
+                SDL_SendTouch((SDL_TouchID) 0, (SDL_FingerID) touchState_old.touch[i].id, SDL_FALSE,
+                              (float) touchState_old.touch[i].position.px / 1280.0f,
+                              (float) touchState_old.touch[i].position.py / 720.0f, 1);
+            }
+        }
+    }
+}
+
+#endif /* SDL_VIDEO_DRIVER_SWITCH */
+
+/* vi: set ts=4 sw=4 expandtab: */

src/video/switch/SDL_switchtouch.h

@@ -0,0 +1,34 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2017 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#ifndef _SDL_switchtouch_h
+#define _SDL_switchtouch_h
+
+#include "../../SDL_internal.h"
+
+/* Touch functions */
+extern void SWITCH_InitTouch(void);
+extern void SWITCH_QuitTouch(void);
+extern void SWITCH_PollTouch(void);
+
+#endif /* _SDL_switchtouch_h */
+
+/* vi: set ts=4 sw=4 expandtab: */

src/video/switch/SDL_switchvideo.c

@@ -27,6 +27,7 @@
 #include "../SDL_sysvideo.h"
 #include "../../events/SDL_keyboard_c.h"
 #include "../../events/SDL_windowevents_c.h"
+#include "SDL_switchtouch.h"
 
 #include <switch.h>
 
@@ -117,11 +118,15 @@ static int SWITCH_VideoInit(_THIS)
     mode.h = 0;
     SDL_AddDisplayMode(&_this->displays[0], &mode);
 
+    // init touch
+    SWITCH_InitTouch();
+
     return 0;
 }
 
 static void SWITCH_VideoQuit(_THIS)
 {
+    SWITCH_QuitTouch();
     gfxExit();
 }
 
@@ -143,6 +148,7 @@ static void SWITCH_PumpEvents(_THIS)
     }
 
     hidScanInput();
+    SWITCH_PollTouch();
 }
 
 static void SWITCH_SetResolution(u32 width, u32 height)