properly match SDL mousebuttons to DOM buttons

3 files changed, 6 insertions, 6 deletions

diff --git a/src/library_sdl.js b/src/library_sdl.js
index 63d6c9da..9ba78ae2 100644
--- a/src/library_sdl.js
+++ b/src/library_sdl.js
@@ -311,7 +311,7 @@ mergeInto(LibraryManager.library, {
           if (event.type != 'mousemove') {
             var down = event.type === 'mousedown';
             {{{ makeSetValue('ptr', 'SDL.structs.MouseButtonEvent.type', 'down ? 0x401 : 0x402', 'i32') }}};
-            {{{ makeSetValue('ptr', 'SDL.structs.MouseButtonEvent.button', 'event.button', 'i8') }}};
+            {{{ makeSetValue('ptr', 'SDL.structs.MouseButtonEvent.button', 'event.button+1', 'i8') }}}; // DOM buttons are 0-2, SDL 1-3
             {{{ makeSetValue('ptr', 'SDL.structs.MouseButtonEvent.state', 'down ? 1 : 0', 'i8') }}};
             {{{ makeSetValue('ptr', 'SDL.structs.MouseButtonEvent.x', 'x', 'i32') }}};
             {{{ makeSetValue('ptr', 'SDL.structs.MouseButtonEvent.y', 'y', 'i32') }}};
diff --git a/tests/runner.py b/tests/runner.py
index 0106df5d..e6a792eb 100755
--- a/tests/runner.py
+++ b/tests/runner.py
@@ -6413,7 +6413,7 @@ f.close()
       open(os.path.join(self.get_dir(), 'pre.js'), 'w').write('''
         function simulateMouseEvent(x, y, button) {
           var event = document.createEvent("MouseEvents");
-          if (button) {
+          if (button >= 0) {
             var event1 = document.createEvent("MouseEvents");
             event1.initMouseEvent('mousedown', true, true, window,
                        1, Module['canvas'].offsetLeft + x, Module['canvas'].offsetTop + y, Module['canvas'].offsetLeft + x, Module['canvas'].offsetTop + y,
diff --git a/tests/sdl_mouse.c b/tests/sdl_mouse.c
index eb731186..a0520839 100644
--- a/tests/sdl_mouse.c
+++ b/tests/sdl_mouse.c
@@ -46,10 +46,10 @@ int main() {
   SDL_Rect rect = { 0, 0, 600, 450 };
   SDL_FillRect(screen, &rect, 0x2244ff00);
 
-  emscripten_run_script("simulateMouseEvent(10, 20, 0)"); // move from 0,0 to 10,20
-  emscripten_run_script("simulateMouseEvent(10, 20, 1)"); // click
-  emscripten_run_script("simulateMouseEvent(30, 77, 0)"); // move some more
-  emscripten_run_script("simulateMouseEvent(30, 77, 2)"); // trigger the end
+  emscripten_run_script("simulateMouseEvent(10, 20, -1)"); // move from 0,0 to 10,20
+  emscripten_run_script("simulateMouseEvent(10, 20, 0)"); // click
+  emscripten_run_script("simulateMouseEvent(30, 77, -1)"); // move some more
+  emscripten_run_script("simulateMouseEvent(30, 77, 1)"); // trigger the end
 
   emscripten_set_main_loop(one, 0);