diff options
Diffstat (limited to 'wintable/new/scroll.h')
| -rw-r--r-- | wintable/new/scroll.h | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/wintable/new/scroll.h b/wintable/new/scroll.h index 81b49c5..1f333a8 100644 --- a/wintable/new/scroll.h +++ b/wintable/new/scroll.h @@ -6,6 +6,7 @@ struct scrollParams { intptr_t length; intptr_t scale; void (*post)(struct table *); + int *wheelCarry; }; static void scrollto(struct table *t, int which, struct scrollParams *p, intptr_t pos) @@ -104,3 +105,26 @@ static void scroll(struct table *t, int which, struct scrollParams *p, WPARAM wP } scrollto(t, which, p, pos); } + +static void wheelscroll(struct table *t, int which, struct scrollParams *p, WPARAM wParam, LPARAM lParam) +{ + int delta; + int lines; + UINT scrollAmount; + + delta = GET_WHEEL_DELTA_WPARAM(wParam); + // TODO make a note of what the appropriate hscroll constant is + if (SystemParametersInfoW(SPI_GETWHEELSCROLLLINES, 0, &scrollAmount, 0) == 0) + // TODO use scrollAmount == 3 instead? + panic("error getting wheel scroll amount in wheelscroll()"); + if (scrollAmount == WHEEL_PAGESCROLL) + scrollAmount = p->pagesize; + if (scrollAmount == 0) // no mouse wheel scrolling (or t->pagesize == 0) + return; + // the rest of this is basically http://blogs.msdn.com/b/oldnewthing/archive/2003/08/07/54615.aspx and http://blogs.msdn.com/b/oldnewthing/archive/2003/08/11/54624.aspx + // see those pages for information on subtleties + delta += *(p->wheelCarry); + lines = delta * ((int) scrollAmount) / WHEEL_DELTA; + *(p->wheelCarry) = delta - lines * WHEEL_DELTA / ((int) scrollAmount); + scrollby(t, which, p, -lines); +} |