diff options
| -rw-r--r-- | src/library_sdl.js | 38 |
1 files changed, 15 insertions, 23 deletions
diff --git a/src/library_sdl.js b/src/library_sdl.js index 77305609..4e44e1d5 100644 --- a/src/library_sdl.js +++ b/src/library_sdl.js @@ -443,23 +443,6 @@ var LibrarySDL = { return false; }, - offsetsTemp: { left: 0, top: 0 }, // temporary object to avoid generating garbage in offsets(). assumes the object is not captured - - offsets: function(element) { - var left = 0; - var top = 0; - - do { - left += element.offsetLeft; - top += element.offsetTop; - } while (element = element.offsetParent) - - var ret = SDL.offsetsTemp; - ret.left = left; - ret.top = top; - return ret; - }, - makeCEvent: function(event, ptr) { if (typeof event === 'number') { // This is a pointer to a native C event that was SDL_PushEvent'ed @@ -541,9 +524,18 @@ var LibrarySDL = { } else { // Otherwise, calculate the movement based on the changes // in the coordinates. - var offsets = SDL.offsets(Module["canvas"]); - var x = event.pageX - offsets.left; - var y = event.pageY - offsets.top; + var rect = Module["canvas"].getBoundingClientRect(); + var x = event.pageX - (window.scrollX + rect.left); + var y = event.pageY - (window.scrollY + rect.top); + + // the canvas might be CSS-scaled compared to its backbuffer; + // SDL-using content will want mouse coordinates in terms + // of backbuffer units. + var cw = Module["canvas"].width; + var ch = Module["canvas"].height; + x = x * (cw / rect.width); + y = y * (ch / rect.height); + var movementX = x - SDL.mouseX; var movementY = y - SDL.mouseY; } @@ -930,11 +922,11 @@ var LibrarySDL = { SDL_WarpMouse: function(x, y) { return; // TODO: implement this in a non-buggy way. Need to keep relative mouse movements correct after calling this - var offsets = SDL.offsets(Module["canvas"]); + var rect = Module["canvas"].getBoundingClientRect(); SDL.events.push({ type: 'mousemove', - pageX: x + offsets.left, - pageY: y + offsets.top + pageX: x + (window.scrollX + rect.left), + pageY: y + (window.scrollY + rect.top) }); }, |