static void
ConstrainSize(WinXSizeHints hints, int *widthp, int *heightp)
{
int minWidth, minHeight, maxWidth, maxHeight, xinc, yinc, delta;
int baseWidth, baseHeight;
int dwidth = *widthp, dheight = *heightp;
if (hints.flags & PMinSize) {
minWidth = hints.min_width;
minHeight = hints.min_height;
}
else if (hints.flags & PBaseSize) {
minWidth = hints.base_width;
minHeight = hints.base_height;
}
else
minWidth = minHeight = 1;
if (hints.flags & PBaseSize) {
baseWidth = hints.base_width;
baseHeight = hints.base_height;
}
else if (hints.flags & PMinSize) {
baseWidth = hints.min_width;
baseHeight = hints.min_height;
}
else
baseWidth = baseHeight = 0;
if (hints.flags & PMaxSize) {
maxWidth = hints.max_width;
maxHeight = hints.max_height;
}
else {
maxWidth = MAXINT;
maxHeight = MAXINT;
}
if (hints.flags & PResizeInc) {
xinc = hints.width_inc;
yinc = hints.height_inc;
}
else
xinc = yinc = 1;
/*
* First, clamp to min and max values
*/
if (dwidth < minWidth)
dwidth = minWidth;
if (dheight < minHeight)
dheight = minHeight;
if (dwidth > maxWidth)
dwidth = maxWidth;
if (dheight > maxHeight)
dheight = maxHeight;
/*
* Second, fit to base + N * inc
*/
dwidth = ((dwidth - baseWidth) / xinc * xinc) + baseWidth;
dheight = ((dheight - baseHeight) / yinc * yinc) + baseHeight;
/*
* Third, adjust for aspect ratio
*/
/*
* The math looks like this:
*
* minAspectX dwidth maxAspectX
* ---------- <= ------- <= ----------
* minAspectY dheight maxAspectY
*
* If that is multiplied out, then the width and height are
* invalid in the following situations:
*
* minAspectX * dheight > minAspectY * dwidth
* maxAspectX * dheight < maxAspectY * dwidth
*
*/
if (hints.flags & PAspect) {
if (hints.min_aspect.x * dheight > hints.min_aspect.y * dwidth) {
delta =
makemult(hints.min_aspect.x * dheight / hints.min_aspect.y -
dwidth, xinc);
if (dwidth + delta <= maxWidth)
dwidth += delta;
else {
delta =
makemult(dheight -
dwidth * hints.min_aspect.y / hints.min_aspect.x,
yinc);
if (dheight - delta >= minHeight)
dheight -= delta;
}
}
if (hints.max_aspect.x * dheight < hints.max_aspect.y * dwidth) {
delta =
makemult(dwidth * hints.max_aspect.y / hints.max_aspect.x -
dheight, yinc);
if (dheight + delta <= maxHeight)
dheight += delta;
else {
delta =
makemult(dwidth -
hints.max_aspect.x * dheight / hints.max_aspect.y,
xinc);
if (dwidth - delta >= minWidth)
dwidth -= delta;
}
}
}
/* Return computed values */
*widthp = dwidth;
*heightp = dheight;
}
/**
*** ConstrainSize()
*** Adjust a given width and height to account for the constraints imposed by
*** size hints.
*** The general algorithm, especially the aspect ratio stuff, is borrowed from
*** uwm's CheckConsistency routine.
**/
void ConstrainSize (XSizeHints *hints, int *widthp, int *heightp)
{
#define makemult(a,b) ((b == 1) ? (a) : (((int)((a) / (b))) * (b)))
int minWidth, minHeight, maxWidth, maxHeight, xinc, yinc, delta;
int baseWidth, baseHeight;
int dwidth = *widthp, dheight = *heightp;
if (hints->flags & PMinSize)
{
minWidth = hints->min_width;
minHeight = hints->min_height;
if (hints->flags & PBaseSize)
{
baseWidth = hints->base_width;
baseHeight = hints->base_height;
}
else
{
baseWidth = hints->min_width;
baseHeight = hints->min_height;
}
}
else if (hints->flags & PBaseSize)
{
minWidth = hints->base_width;
minHeight = hints->base_height;
baseWidth = hints->base_width;
baseHeight = hints->base_height;
}
else
{
minWidth = 1;
minHeight = 1;
baseWidth = 1;
baseHeight = 1;
}
if (hints->flags & PMaxSize)
{
maxWidth = hints->max_width;
maxHeight = hints->max_height;
}
else
{
maxWidth = 32767;
maxHeight = 32767;
}
if (hints->flags & PResizeInc)
{
xinc = hints->width_inc;
yinc = hints->height_inc;
}
else
{
xinc = 1;
yinc = 1;
}
/*
* First, clamp to min and max values
*/
if (dwidth < minWidth)
{
dwidth = minWidth;
}
if (dheight < minHeight)
{
dheight = minHeight;
}
if (dwidth > maxWidth)
{
dwidth = maxWidth;
}
if (dheight > maxHeight)
{
dheight = maxHeight;
}
/*
* Second, fit to base + N * inc
*/
dwidth = ((dwidth - baseWidth) / xinc * xinc) + baseWidth;
dheight = ((dheight - baseHeight) / yinc * yinc) + baseHeight;
/*
* Third, adjust for aspect ratio
*/
#define maxAspectX hints->max_aspect.x
#define maxAspectY hints->max_aspect.y
#define minAspectX hints->min_aspect.x
#define minAspectY hints->min_aspect.y
/*
* The math looks like this:
*
* minAspectX dwidth maxAspectX
* ---------- <= ------- <= ----------
* minAspectY dheight maxAspectY
*
* If that is multiplied out, then the width and height are
* invalid in the following situations:
*
* minAspectX * dheight > minAspectY * dwidth
* maxAspectX * dheight < maxAspectY * dwidth
*
*/
if (hints->flags & PAspect)
{
if (minAspectX * dheight > minAspectY * dwidth)
{
delta = makemult(
minAspectX * dheight / minAspectY - dwidth,
xinc);
if (dwidth + delta <= maxWidth)
{
dwidth += delta;
}
else
{
delta = makemult(
dheight - minAspectY*dwidth/minAspectX,
yinc);
if (dheight - delta >= minHeight)
{
dheight -= delta;
}
}
}
if (maxAspectX * dheight < maxAspectY * dwidth)
{
delta = makemult(
dwidth * maxAspectY / maxAspectX - dheight,
yinc);
if (dheight + delta <= maxHeight)
{
dheight += delta;
}
else
{
delta = makemult(
dwidth - maxAspectX*dheight/maxAspectY,
xinc);
if (dwidth - delta >= minWidth)
{
dwidth -= delta;
}
}
}
}
*widthp = dwidth;
*heightp = dheight;
return;
#undef makemult
#undef maxAspectX
#undef maxAspectY
#undef minAspectX
#undef minAspectY
}
