040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync/*
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * Copyright © 2004 Keith Packard
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync *
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * Permission to use, copy, modify, distribute, and sell this software and its
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * documentation for any purpose is hereby granted without fee, provided that
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * the above copyright notice appear in all copies and that both that
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * copyright notice and this permission notice appear in supporting
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * documentation, and that the name of Keith Packard not be used in
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * advertising or publicity pertaining to distribution of the software without
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * specific, written prior permission. Keith Packard makes no
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * representations about the suitability of this software for any purpose. It
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * is provided "as is" without express or implied warranty.
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync *
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * PERFORMANCE OF THIS SOFTWARE.
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync */
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#ifndef _RENDEREDGE_H_
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#define _RENDEREDGE_H_
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#include "picturestr.h"
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#define MAX_ALPHA(n) ((1 << (n)) - 1)
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#define N_Y_FRAC(n) ((n) == 1 ? 1 : (1 << ((n)/2)) - 1)
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#define N_X_FRAC(n) ((1 << ((n)/2)) + 1)
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#define STEP_Y_SMALL(n) (xFixed1 / N_Y_FRAC(n))
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#define STEP_Y_BIG(n) (xFixed1 - (N_Y_FRAC(n) - 1) * STEP_Y_SMALL(n))
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#define Y_FRAC_FIRST(n) (STEP_Y_SMALL(n) / 2)
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#define Y_FRAC_LAST(n) (Y_FRAC_FIRST(n) + (N_Y_FRAC(n) - 1) * STEP_Y_SMALL(n))
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#define STEP_X_SMALL(n) (xFixed1 / N_X_FRAC(n))
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#define STEP_X_BIG(n) (xFixed1 - (N_X_FRAC(n) - 1) * STEP_X_SMALL(n))
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#define X_FRAC_FIRST(n) (STEP_X_SMALL(n) / 2)
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#define X_FRAC_LAST(n) (X_FRAC_FIRST(n) + (N_X_FRAC(n) - 1) * STEP_X_SMALL(n))
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#define RenderSamplesX(x,n) ((n) == 1 ? 0 : (xFixedFrac (x) + X_FRAC_FIRST(n)) / STEP_X_SMALL(n))
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync/*
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * An edge structure. This represents a single polygon edge
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * and can be quickly stepped across small or large gaps in the
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * sample grid
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync */
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsynctypedef pixman_edge_t RenderEdge;
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync/*
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * Step across a small sample grid gap
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync */
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#define RenderEdgeStepSmall(edge) { \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync edge->x += edge->stepx_small; \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync edge->e += edge->dx_small; \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync if (edge->e > 0) \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync { \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync edge->e -= edge->dy; \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync edge->x += edge->signdx; \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync } \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync}
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync/*
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync * Step across a large sample grid gap
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync */
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#define RenderEdgeStepBig(edge) { \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync edge->x += edge->stepx_big; \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync edge->e += edge->dx_big; \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync if (edge->e > 0) \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync { \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync edge->e -= edge->dy; \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync edge->x += edge->signdx; \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync } \
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync}
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsyncxFixed
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsyncRenderSampleCeilY (xFixed y, int bpp);
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsyncxFixed
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsyncRenderSampleFloorY (xFixed y, int bpp);
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsyncvoid
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsyncRenderEdgeStep (RenderEdge *e, int n);
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsyncvoid
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsyncRenderEdgeInit (RenderEdge *e,
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync int bpp,
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync xFixed y_start,
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync xFixed x_top,
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync xFixed y_top,
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync xFixed x_bot,
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync xFixed y_bot);
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsyncvoid
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsyncRenderLineFixedEdgeInit (RenderEdge *e,
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync int bpp,
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync xFixed y,
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync xLineFixed *line,
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync int x_off,
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync int y_off);
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync
040abec2534dadc53ebc8fa378ef03f4feecb7dbvboxsync#endif /* _RENDEREDGE_H_ */