tornavis/intern/ghost/test/multitest/ScrollBar.c

137 lines
2.9 KiB
C

/* SPDX-FileCopyrightText: 2001-2002 NaN Holding BV. All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0-or-later */
#include <stdlib.h>
#include <math.h>
#include "MEM_guardedalloc.h"
#include "Basic.h"
#include "ScrollBar.h"
struct _ScrollBar {
int rect[2][2];
float thumbpos, thumbpct;
int inset;
int minthumb;
int scrolling;
float scrolloffs;
};
static int scrollbar_get_thumbH(ScrollBar *sb)
{
int scrollable_h = rect_height(sb->rect) - 2 * sb->inset;
return clamp_i(sb->thumbpct * scrollable_h, sb->minthumb, scrollable_h);
}
static int scrollbar_get_thumbableH(ScrollBar *sb)
{
int scrollable_h = rect_height(sb->rect) - 2 * sb->inset;
int thumb_h = scrollbar_get_thumbH(sb);
return scrollable_h - thumb_h;
}
static float scrollbar_co_to_pos(ScrollBar *sb, int yco)
{
int thumb_h = scrollbar_get_thumbH(sb);
int thumbable_h = scrollbar_get_thumbableH(sb);
int thumbable_y = (sb->rect[0][1] + sb->inset) + thumb_h / 2;
return (float)(yco - thumbable_y) / thumbable_h;
}
/**/
ScrollBar *scrollbar_new(int inset, int minthumb)
{
ScrollBar *sb = MEM_callocN(sizeof(*sb), "scrollbar_new");
sb->inset = inset;
sb->minthumb = minthumb;
return sb;
}
void scrollbar_get_thumb(ScrollBar *sb, int thumb_r[2][2])
{
int thumb_h = scrollbar_get_thumbH(sb);
int thumbable_h = scrollbar_get_thumbableH(sb);
thumb_r[0][0] = sb->rect[0][0] + sb->inset;
thumb_r[1][0] = sb->rect[1][0] - sb->inset;
thumb_r[0][1] = sb->rect[0][1] + sb->inset + sb->thumbpos * thumbable_h;
thumb_r[1][1] = thumb_r[0][1] + thumb_h;
}
int scrollbar_is_scrolling(ScrollBar *sb)
{
return sb->scrolling;
}
int scrollbar_contains_pt(ScrollBar *sb, int pt[2])
{
return rect_contains_pt(sb->rect, pt);
}
void scrollbar_start_scrolling(ScrollBar *sb, int yco)
{
int thumb_h_2 = scrollbar_get_thumbH(sb) / 2;
int thumbable_h = scrollbar_get_thumbableH(sb);
float npos = scrollbar_co_to_pos(sb, yco);
sb->scrolloffs = sb->thumbpos - npos;
if (fabs(sb->scrolloffs) >= (float)thumb_h_2 / thumbable_h) {
sb->scrolloffs = 0.0;
}
sb->scrolling = 1;
sb->thumbpos = clamp_f(npos + sb->scrolloffs, 0.0, 1.0);
}
void scrollbar_keep_scrolling(ScrollBar *sb, int yco)
{
float npos = scrollbar_co_to_pos(sb, yco);
sb->thumbpos = clamp_f(npos + sb->scrolloffs, 0.0, 1.0);
}
void scrollbar_stop_scrolling(ScrollBar *sb)
{
sb->scrolling = 0;
sb->scrolloffs = 0.0;
}
void scrollbar_set_thumbpct(ScrollBar *sb, float pct)
{
sb->thumbpct = pct;
}
void scrollbar_set_thumbpos(ScrollBar *sb, float pos)
{
sb->thumbpos = clamp_f(pos, 0.0, 1.0);
}
void scrollbar_set_rect(ScrollBar *sb, int rect[2][2])
{
rect_copy(sb->rect, rect);
}
float scrollbar_get_thumbpct(ScrollBar *sb)
{
return sb->thumbpct;
}
float scrollbar_get_thumbpos(ScrollBar *sb)
{
return sb->thumbpos;
}
void scrollbar_get_rect(ScrollBar *sb, int rect_r[2][2])
{
rect_copy(rect_r, sb->rect);
}
void scrollbar_free(ScrollBar *sb)
{
MEM_freeN(sb);
}