From 6625203514e5a12a76ba968331bb3c6beea0c109 Mon Sep 17 00:00:00 2001
From: Sylvain Becker <sylvain.becker@gmail.com>
Date: Tue, 9 Jul 2019 11:46:42 +0200
Subject: [PATCH] SDL_Mouse/Touch: discard synthetic events when hints are not
 set. Those are generated/flagged by platform layer.

---
 src/events/SDL_mouse.c | 14 ++++++++++++++
 src/events/SDL_touch.c | 22 ++++++++++++++++++++--
 2 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/src/events/SDL_mouse.c b/src/events/SDL_mouse.c
index c423c56e542ee..0ecb3cc77c533 100644
--- a/src/events/SDL_mouse.c
+++ b/src/events/SDL_mouse.c
@@ -338,6 +338,13 @@ SDL_PrivateSendMouseMotion(SDL_Window * window, SDL_MouseID mouseID, int relativ
         }
     }
 
+    /* SDL_HINT_TOUCH_MOUSE_EVENTS: if not set, discard synthetic mouse events coming from platform layer */
+    if (mouse->touch_mouse_events == 0) {
+        if (mouseID == SDL_TOUCH_MOUSEID) {
+            return 0;
+        }
+    }
+
     if (mouseID != SDL_TOUCH_MOUSEID && mouse->relative_mode_warp) {
         int center_x = 0, center_y = 0;
         SDL_GetWindowSize(window, &center_x, &center_y);
@@ -499,6 +506,13 @@ SDL_PrivateSendMouseButton(SDL_Window * window, SDL_MouseID mouseID, Uint8 state
         }
     }
 
+    /* SDL_HINT_TOUCH_MOUSE_EVENTS: if not set, discard synthetic mouse events coming from platform layer */
+    if (mouse->touch_mouse_events == 0) {
+        if (mouseID == SDL_TOUCH_MOUSEID) {
+            return 0;
+        }
+    }
+
     /* Figure out which event to perform */
     switch (state) {
     case SDL_PRESSED:
diff --git a/src/events/SDL_touch.c b/src/events/SDL_touch.c
index 6cf576dc1dc84..150acb8220183 100644
--- a/src/events/SDL_touch.c
+++ b/src/events/SDL_touch.c
@@ -244,16 +244,18 @@ SDL_SendTouch(SDL_TouchID id, SDL_FingerID fingerid,
 {
     int posted;
     SDL_Finger *finger;
+    SDL_Mouse *mouse;
 
     SDL_Touch* touch = SDL_GetTouch(id);
     if (!touch) {
         return -1;
     }
 
+    mouse = SDL_GetMouse();
+
 #if SYNTHESIZE_TOUCH_TO_MOUSE
     /* SDL_HINT_TOUCH_MOUSE_EVENTS: controlling whether touch events should generate synthetic mouse events */
     {
-        SDL_Mouse *mouse = SDL_GetMouse();
         if (mouse->touch_mouse_events) {
             /* FIXME: maybe we should only restrict to a few SDL_TouchDeviceType */
             if (id != SDL_MOUSE_TOUCHID) {
@@ -301,6 +303,13 @@ SDL_SendTouch(SDL_TouchID id, SDL_FingerID fingerid,
     }
 #endif
 
+    /* SDL_HINT_MOUSE_TOUCH_EVENTS: if not set, discard synthetic touch events coming from platform layer */
+    if (mouse->mouse_touch_events == 0) {
+        if (id == SDL_MOUSE_TOUCHID) {
+            return 0;
+        }
+    }
+
     finger = SDL_GetFinger(touch, fingerid);
     if (down) {
         if (finger) {
@@ -357,6 +366,7 @@ SDL_SendTouchMotion(SDL_TouchID id, SDL_FingerID fingerid,
 {
     SDL_Touch *touch;
     SDL_Finger *finger;
+    SDL_Mouse *mouse;
     int posted;
     float xrel, yrel, prel;
 
@@ -365,10 +375,11 @@ SDL_SendTouchMotion(SDL_TouchID id, SDL_FingerID fingerid,
         return -1;
     }
 
+    mouse = SDL_GetMouse();
+
 #if SYNTHESIZE_TOUCH_TO_MOUSE
     /* SDL_HINT_TOUCH_MOUSE_EVENTS: controlling whether touch events should generate synthetic mouse events */
     {
-        SDL_Mouse *mouse = SDL_GetMouse();
         if (mouse->touch_mouse_events) {
             if (id != SDL_MOUSE_TOUCHID) {
                 SDL_Window *window = SDL_GetMouseFocus();
@@ -388,6 +399,13 @@ SDL_SendTouchMotion(SDL_TouchID id, SDL_FingerID fingerid,
     }
 #endif
 
+    /* SDL_HINT_MOUSE_TOUCH_EVENTS: if not set, discard synthetic touch events coming from platform layer */
+    if (mouse->mouse_touch_events == 0) {
+        if (id == SDL_MOUSE_TOUCHID) {
+            return 0;
+        }
+    }
+
     finger = SDL_GetFinger(touch,fingerid);
     if (!finger) {
         return SDL_SendTouch(id, fingerid, SDL_TRUE, x, y, pressure);