michael@0: /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "gfxRect.h"
michael@0: 
michael@0: #include "nsMathUtils.h"
michael@0: 
michael@0: static bool
michael@0: WithinEpsilonOfInteger(gfxFloat aX, gfxFloat aEpsilon)
michael@0: {
michael@0:     return fabs(NS_round(aX) - aX) <= fabs(aEpsilon);
michael@0: }
michael@0: 
michael@0: bool
michael@0: gfxRect::WithinEpsilonOfIntegerPixels(gfxFloat aEpsilon) const
michael@0: {
michael@0:     NS_ASSERTION(-0.5 < aEpsilon && aEpsilon < 0.5, "Nonsense epsilon value");
michael@0:     return (WithinEpsilonOfInteger(x, aEpsilon) &&
michael@0:             WithinEpsilonOfInteger(y, aEpsilon) &&
michael@0:             WithinEpsilonOfInteger(width, aEpsilon) &&
michael@0:             WithinEpsilonOfInteger(height, aEpsilon));
michael@0: }
michael@0: 
michael@0: /* Clamp r to CAIRO_COORD_MIN .. CAIRO_COORD_MAX
michael@0:  * these are to be device coordinates.
michael@0:  *
michael@0:  * Cairo is currently using 24.8 fixed point,
michael@0:  * so -2^24 .. 2^24-1 is our valid
michael@0:  */
michael@0: 
michael@0: #define CAIRO_COORD_MAX (16777215.0)
michael@0: #define CAIRO_COORD_MIN (-16777216.0)
michael@0: 
michael@0: void
michael@0: gfxRect::Condition()
michael@0: {
michael@0:     // if either x or y is way out of bounds;
michael@0:     // note that we don't handle negative w/h here
michael@0:     if (x > CAIRO_COORD_MAX) {
michael@0:         x = CAIRO_COORD_MAX;
michael@0:         width = 0.0;
michael@0:     } 
michael@0: 
michael@0:     if (y > CAIRO_COORD_MAX) {
michael@0:         y = CAIRO_COORD_MAX;
michael@0:         height = 0.0;
michael@0:     }
michael@0: 
michael@0:     if (x < CAIRO_COORD_MIN) {
michael@0:         width += x - CAIRO_COORD_MIN;
michael@0:         if (width < 0.0)
michael@0:             width = 0.0;
michael@0:         x = CAIRO_COORD_MIN;
michael@0:     }
michael@0: 
michael@0:     if (y < CAIRO_COORD_MIN) {
michael@0:         height += y - CAIRO_COORD_MIN;
michael@0:         if (height < 0.0)
michael@0:             height = 0.0;
michael@0:         y = CAIRO_COORD_MIN;
michael@0:     }
michael@0: 
michael@0:     if (x + width > CAIRO_COORD_MAX) {
michael@0:         width = CAIRO_COORD_MAX - x;
michael@0:     }
michael@0: 
michael@0:     if (y + height > CAIRO_COORD_MAX) {
michael@0:         height = CAIRO_COORD_MAX - y;
michael@0:     }
michael@0: }
michael@0: