whytofly
/
qt6-bb10
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Fix smooth scaling of large QImages 

Task-number: QTBUG-13448
Change-Id: Ie76f5b5deefabeae93ab17eb866aea303692f5ac
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
bb10
Alex Blasche 2014-09-22 11:22:17 +02:00 committed by Allan Sandfeld Jensen
parent a72d585f9b
commit 342533864b
1 changed files with 13 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
src/gui/painting/qimagescale.cpp
View File

@ -143,8 +143,8 @@ unsigned int** QImageScale::qimageCalcYPoints(unsigned int *src,
int sw, int sh, int dh)
{
unsigned int **p;
int i, j = 0;
int val, inc, rv = 0;
int i, j = 0, rv = 0;
qint64 val, inc;
if(dh < 0){
dh = -dh;
@ -154,9 +154,9 @@ unsigned int** QImageScale::qimageCalcYPoints(unsigned int *src,
int up = qAbs(dh) >= sh;
val = up ? 0x8000 * sh / dh - 0x8000 : 0;
inc = (sh << 16) / dh;
inc = (((qint64)sh) << 16) / dh;
for(i = 0; i < dh; i++){
p[j++] = src + qMax(0, val >> 16) * sw;
p[j++] = src + qMax(0LL, val >> 16) * sw;
val += inc;
}
if(rv){
@ -171,8 +171,8 @@ unsigned int** QImageScale::qimageCalcYPoints(unsigned int *src,
int* QImageScale::qimageCalcXPoints(int sw, int dw)
{
int *p, i, j = 0;
int val, inc, rv = 0;
int *p, i, j = 0, rv = 0;
qint64 val, inc;
if(dw < 0){
dw = -dw;
@ -182,9 +182,9 @@ int* QImageScale::qimageCalcXPoints(int sw, int dw)
int up = qAbs(dw) >= sw;
val = up ? 0x8000 * sw / dw - 0x8000 : 0;
inc = (sw << 16) / dw;
inc = (((qint64)sw) << 16) / dw;
for(i = 0; i < dw; i++){
p[j++] = qMax(0, val >> 16);
p[j++] = qMax(0LL, val >> 16);
val += inc;
}
@ -210,10 +210,10 @@ int* QImageScale::qimageCalcApoints(int s, int d, int up)
/* scaling up */
if(up){
int val, inc;
qint64 val, inc;
val = 0x8000 * s / d - 0x8000;
inc = (s << 16) / d;
inc = (((qint64)s) << 16) / d;
for(i = 0; i < d; i++){
int pos = val >> 16;
if (pos < 0)
@ -227,9 +227,10 @@ int* QImageScale::qimageCalcApoints(int s, int d, int up)
}
/* scaling down */
else{
int val, inc, ap, Cp;
qint64 val, inc;
int ap, Cp;
val = 0;
inc = (s << 16) / d;
inc = (((qint64)s) << 16) / d;
Cp = ((d << 14) / s) + 1;
for(i = 0; i < d; i++){
ap = ((0x100 - ((val >> 8) & 0xff)) * Cp) >> 8;