gecko-dev/gfx/thebes/gfxRect.cpp
2012-05-21 12:12:37 +01:00

74 lines
1.8 KiB
C++

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "gfxRect.h"
#include "nsMathUtils.h"
static bool
WithinEpsilonOfInteger(gfxFloat aX, gfxFloat aEpsilon)
{
return fabs(NS_round(aX) - aX) <= fabs(aEpsilon);
}
bool
gfxRect::WithinEpsilonOfIntegerPixels(gfxFloat aEpsilon) const
{
NS_ASSERTION(-0.5 < aEpsilon && aEpsilon < 0.5, "Nonsense epsilon value");
return (WithinEpsilonOfInteger(x, aEpsilon) &&
WithinEpsilonOfInteger(y, aEpsilon) &&
WithinEpsilonOfInteger(width, aEpsilon) &&
WithinEpsilonOfInteger(height, aEpsilon));
}
/* Clamp r to CAIRO_COORD_MIN .. CAIRO_COORD_MAX
* these are to be device coordinates.
*
* Cairo is currently using 24.8 fixed point,
* so -2^24 .. 2^24-1 is our valid
*/
#define CAIRO_COORD_MAX (16777215.0)
#define CAIRO_COORD_MIN (-16777216.0)
void
gfxRect::Condition()
{
// if either x or y is way out of bounds;
// note that we don't handle negative w/h here
if (x > CAIRO_COORD_MAX) {
x = CAIRO_COORD_MAX;
width = 0.0;
}
if (y > CAIRO_COORD_MAX) {
y = CAIRO_COORD_MAX;
height = 0.0;
}
if (x < CAIRO_COORD_MIN) {
width += x - CAIRO_COORD_MIN;
if (width < 0.0)
width = 0.0;
x = CAIRO_COORD_MIN;
}
if (y < CAIRO_COORD_MIN) {
height += y - CAIRO_COORD_MIN;
if (height < 0.0)
height = 0.0;
y = CAIRO_COORD_MIN;
}
if (x + width > CAIRO_COORD_MAX) {
width = CAIRO_COORD_MAX - x;
}
if (y + height > CAIRO_COORD_MAX) {
height = CAIRO_COORD_MAX - y;
}
}