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The branch, master has been updated via 582174a303ed68281404b7f09beeba72d8d80a17 (commit) from 16a50bf6b0c956641c452653bd38621d668aef66 (commit) Those revisions listed above that are new to this repository have not appeared on any other notification email; so we list those revisions in full, below. - Log ----------------------------------------------------------------- http://repo.or.cz/w/gfxprim.git/commit/582174a303ed68281404b7f09beeba72d8d80... commit 582174a303ed68281404b7f09beeba72d8d80a17 Author: BlueBear <jiri.bluebear.dluhos@gmail.com> Date: Sun May 1 23:14:42 2011 +0200 Initial implementation of convex polygon drawing. diff --git a/core/GP.h b/core/GP.h index 29be3f5..1be9710 100644 --- a/core/GP.h +++ b/core/GP.h @@ -58,6 +58,7 @@ #include "GP_FillCircle.h" #include "GP_Ellipse.h" #include "GP_FillEllipse.h" +#include "GP_Polygon.h" #include "GP_Symbol.h" /* fonts */ diff --git a/core/GP_Polygon.c b/core/GP_Polygon.c new file mode 100644 index 0000000..845825b --- /dev/null +++ b/core/GP_Polygon.c @@ -0,0 +1,161 @@ +/***************************************************************************** + * This file is part of gfxprim library. * + * * + * Gfxprim is free software; you can redistribute it and/or * + * modify it under the terms of the GNU Lesser General Public * + * License as published by the Free Software Foundation; either * + * version 2.1 of the License, or (at your option) any later version. * + * * + * Gfxprim is distributed in the hope that it will be useful, * + * but WITHOUT ANY WARRANTY; without even the implied warranty of * + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * + * Lesser General Public License for more details. * + * * + * You should have received a copy of the GNU Lesser General Public * + * License along with gfxprim; if not, write to the Free Software * + * Foundation, Inc., 51 Franklin Street, Fifth Floor, * + * Boston, MA 02110-1301 USA * + * * + * Copyright (C) 2009-2010 Jiri "BlueBear" Dluhos * + * <jiri.bluebear.dluhos@gmail.com> * + * * + * Copyright (C) 2009-2010 Cyril Hrubis <metan@ucw.cz> * + * * + *****************************************************************************/ + +#include "GP.h" + +#include <limits.h> + +struct GP_PolygonEdge { + int startx, starty; + int endx, endy; + int dx, dy, sx; + struct GP_PolygonEdge *next; +}; + +struct GP_Polygon { + struct GP_PolygonEdge *edges; + int ymin, ymax; +}; + +static struct GP_PolygonEdge *GP_NewEdge(int x1, int y1, int x2, int y2) +{ + struct GP_PolygonEdge *edge = malloc(sizeof(*edge)); + if (y1 < y2) { /* coords are top-down, correct */ + edge->startx = x1; + edge->starty = y1; + edge->endx = x2; + edge->endy = y2; + } else { /* coords are bottom-up, flip them */ + edge->startx = x2; + edge->starty = y2; + edge->endx = x1; + edge->endy = y1; + } + + edge->dx = abs(edge->endx - edge->startx); + edge->dy = edge->endy - edge->starty; + edge->sx = (edge->endx >= edge->startx) ? 1 : -1; + + return edge; +} + +static void GP_InsertEdge(struct GP_Polygon *poly, struct GP_PolygonEdge *new_edge) +{ + struct GP_PolygonEdge *cur_edge = poly->edges; + + poly->ymin = GP_MIN(poly->ymin, new_edge->starty); + poly->ymax = GP_MAX(poly->ymax, new_edge->endy); + + if (cur_edge == NULL || cur_edge->starty > new_edge->starty) { + new_edge->next = cur_edge; + poly->edges = new_edge; + return; + } + + for (;;) { + if (cur_edge->next == NULL || cur_edge->next->starty > new_edge->starty) { + new_edge->next = cur_edge->next; + cur_edge->next = new_edge; + return; + } + cur_edge = cur_edge->next; + } +} + +static struct GP_Polygon *GP_NewPolygon(void) +{ + struct GP_Polygon *poly = malloc(sizeof(struct GP_Polygon)); + poly->edges = NULL; + poly->ymin = INT_MAX; + poly->ymax = 0; + return poly; +} + +static void GP_LoadPolygon(struct GP_Polygon *poly, int vertex_count, int *xy) +{ + int i; + int coord_count = 2*vertex_count - 2; + for (i = 0; i < coord_count; i+=2) { + + + if (xy[i+1] == xy[i+3]) { + continue; /* skip horizontal edges */ + } + + struct GP_PolygonEdge *edge = GP_NewEdge(xy[i], + xy[i+1], xy[i+2], xy[i+3]); + + GP_InsertEdge(poly, edge); + } + + /* add the closing edge */ + if (xy[1] != xy[i+1]) { + struct GP_PolygonEdge *edge = GP_NewEdge(xy[i], xy[i+1], + xy[0], xy[1]); + GP_InsertEdge(poly, edge); + } +} + +static void GP_FreePolygon(struct GP_Polygon *poly) +{ + struct GP_PolygonEdge *edge = poly->edges; + for (;;) { + struct GP_PolygonEdge *next_edge = edge->next; + free(edge); + if (next_edge == NULL) + break; + edge = next_edge; + } + free(poly); +} + +void GP_FillPolygon(GP_Context *context, int vertex_count, int *xy, GP_Pixel pixel) +{ + struct GP_Polygon *poly = GP_NewPolygon(); + GP_LoadPolygon(poly, vertex_count, xy); + + int y; + for (y = poly->ymin; y <= poly->ymax; y++) { + int startx = INT_MAX; + int endx = 0; + + struct GP_PolygonEdge *edge; + for (edge = poly->edges; edge; edge = edge->next) { + if (y >= edge->starty && y <= edge->endy) { + int edge_y = y - edge->starty; + int edge_x; + for (edge_x = edge->sx > 0 ? edge->startx: edge->endx; + edge->startx*edge->dy + edge->sx*edge_y*edge->dx - edge_x*edge->dy > 0; + edge_x++); + startx = GP_MIN(startx, edge_x); + endx = GP_MAX(endx, edge_x); + } + } + + GP_HLine(context, startx, endx, y, pixel); + } + + GP_FreePolygon(poly); +} diff --git a/core/GP.h b/core/GP_Polygon.h similarity index 69% copy from core/GP.h copy to core/GP_Polygon.h index 29be3f5..49c11ab 100644 --- a/core/GP.h +++ b/core/GP_Polygon.h @@ -23,47 +23,11 @@ * * *****************************************************************************/ -#ifndef GP_H -#define GP_H +#ifndef GP_FILL_POLYGON_H +#define GP_FILL_POLYGON_H -#include <stdint.h> - -/* basic definitions and structures */ -#include "GP_Common.h" -#include "GP_Transform.h" #include "GP_Context.h" -/* semi-public, low-level drawing API */ -#include "GP_WritePixel.h" - -/* colors */ -#include "GP_Color.h" -#include "GP_Palette.h" - -/* public drawing API */ -#include "GP_Fill.h" -#include "GP_GetPixel.h" -#include "GP_PutPixel.h" -#include "GP_HLine.h" -#include "GP_VLine.h" -#include "GP_Line.h" -#include "GP_LineTrack.h" -#include "GP_Rect.h" -#include "GP_FillRect.h" -#include "GP_Triangle.h" -#include "GP_FillTriangle.h" -#include "GP_Tetragon.h" -#include "GP_FillTetragon.h" -#include "GP_Circle.h" -#include "GP_FillCircle.h" -#include "GP_Ellipse.h" -#include "GP_FillEllipse.h" -#include "GP_Symbol.h" - -/* fonts */ -#include "GP_Font.h" -#include "GP_TextStyle.h" -#include "GP_TextMetric.h" -#include "GP_Text.h" +void GP_FillPolygon(GP_Context *context, int vertex_count, int *xy, GP_Pixel pixel); -#endif /* GP_H */ +#endif /* GP_RECT_H */ ----------------------------------------------------------------------- Summary of changes: core/GP.h | 1 + core/GP_Polygon.c | 161 ++++++++++++++++++++++++++++++++++++++ core/{GP_Fill.h => GP_Polygon.h} | 8 +- 3 files changed, 166 insertions(+), 4 deletions(-) create mode 100644 core/GP_Polygon.c copy core/{GP_Fill.h => GP_Polygon.h} (92%) repo.or.cz automatic notification. 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