Commit 59574fe2f0a7b2a189f1129abcc83d306cfdf830
2018-06-24T13:57:22
x11: Normalize x11xinput2 touch x to be 1.0 at width (thanks, Zach!). "Applications (such as SDL's testgesture) do "event.tfinger.x * window_width" to find window coord. Currently the X11 XInput2 backend expects application to do "event.tfinger.x * (window_width-1)" instead. X11 XInput2 touch events are normalized so x is 1.0 at "width - 1" but other SDL backends appear to have x be 1.0 at "width". Same issue for touch event y with regards to height." Fixes Bugzilla #4183.
diff --git a/src/video/x11/SDL_x11xinput2.c b/src/video/x11/SDL_x11xinput2.c
index 06a8937..e8bb141 100644
--- a/src/video/x11/SDL_x11xinput2.c
+++ b/src/video/x11/SDL_x11xinput2.c
@@ -83,16 +83,8 @@ xinput2_normalize_touch_coordinates(SDL_VideoData *videodata, Window window,
for (i = 0; i < videodata->numwindows; i++) {
SDL_WindowData *d = videodata->windowlist[i];
if (d->xwindow == window) {
- if (d->window->w == 1) {
- *out_x = 0.5f;
- } else {
- *out_x = in_x / (d->window->w - 1);
- }
- if (d->window->h == 1) {
- *out_y = 0.5f;
- } else {
- *out_y = in_y / (d->window->h - 1);
- }
+ *out_x = in_x / d->window->w;
+ *out_y = in_y / d->window->h;
return;
}
}