From d05ae1941c61e571644c9451e6a9bd69943ac8dc Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <icculus@icculus.org>
Date: Fri, 12 Aug 2016 19:59:00 -0400
Subject: [PATCH] emscripten: send fake mouse events for touches, like other
 targets do.

(This really should be handled at the higher level and not in the individual
targets, but this fixes the immediate bug.)
---
 src/video/emscripten/SDL_emscriptenevents.c | 19 ++++++++++++++++---
 src/video/emscripten/SDL_emscriptenvideo.h  |  4 ++++
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/src/video/emscripten/SDL_emscriptenevents.c b/src/video/emscripten/SDL_emscriptenevents.c
index 0f915c6f3..306ec552a 100644
--- a/src/video/emscripten/SDL_emscriptenevents.c
+++ b/src/video/emscripten/SDL_emscriptenevents.c
@@ -391,11 +391,24 @@ Emscripten_HandleTouch(int eventType, const EmscriptenTouchEvent *touchEvent, vo
         x = touchEvent->touches[i].canvasX / (float)window_data->windowed_width;
         y = touchEvent->touches[i].canvasY / (float)window_data->windowed_height;
 
-        if (eventType == EMSCRIPTEN_EVENT_TOUCHMOVE) {
-            SDL_SendTouchMotion(deviceId, id, x, y, 1.0f);
-        } else if (eventType == EMSCRIPTEN_EVENT_TOUCHSTART) {
+        if (eventType == EMSCRIPTEN_EVENT_TOUCHSTART) {
+            if (!window_data->finger_touching) {
+                window_data->finger_touching = SDL_TRUE;
+                window_data->first_finger = id;
+                SDL_SendMouseMotion(window_data->window, SDL_TOUCH_MOUSEID, 0, x, y);
+                SDL_SendMouseButton(window_data->window, SDL_TOUCH_MOUSEID, SDL_PRESSED, SDL_BUTTON_LEFT);
+            }
             SDL_SendTouch(deviceId, id, SDL_TRUE, x, y, 1.0f);
+        } else if (eventType == EMSCRIPTEN_EVENT_TOUCHMOVE) {
+            if ((window_data->finger_touching) && (window_data->first_finger == id)) {
+                SDL_SendMouseMotion(window_data->window, SDL_TOUCH_MOUSEID, 0, x, y);
+            }
+            SDL_SendTouchMotion(deviceId, id, x, y, 1.0f);
         } else {
+            if ((window_data->finger_touching) && (window_data->first_finger == id)) {
+                SDL_SendMouseButton(window_data->window, SDL_TOUCH_MOUSEID, SDL_RELEASED, SDL_BUTTON_LEFT);
+                window_data->finger_touching = SDL_FALSE;
+            }
             SDL_SendTouch(deviceId, id, SDL_FALSE, x, y, 1.0f);
         }
     }
diff --git a/src/video/emscripten/SDL_emscriptenvideo.h b/src/video/emscripten/SDL_emscriptenvideo.h
index e824de34f..49b0b356b 100644
--- a/src/video/emscripten/SDL_emscriptenvideo.h
+++ b/src/video/emscripten/SDL_emscriptenvideo.h
@@ -24,6 +24,7 @@
 #define _SDL_emscriptenvideo_h
 
 #include "../SDL_sysvideo.h"
+#include "../../events/SDL_touch_c.h"
 #include <emscripten/emscripten.h>
 #include <emscripten/html5.h>
 
@@ -45,6 +46,9 @@ typedef struct SDL_WindowData
     SDL_bool external_size;
 
     int requested_fullscreen_mode;
+
+    SDL_bool finger_touching;  /* for mapping touch events to mice */
+    SDL_FingerID first_finger;
 } SDL_WindowData;
 
 #endif /* _SDL_emscriptenvideo_h */