lib/art/art_render_gradient.h

   1 /*
   2  * art_render_gradient.h: Gradient image source for modular rendering.
   3  *
   4  * Libart_LGPL - library of basic graphic primitives
   5  * Copyright (C) 2000 Raph Levien
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Library General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Library General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Library General Public
  18  * License along with this library; if not, write to the
  19  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20  * Boston, MA 02111-1307, USA.
  21  *
  22  * Authors: Raph Levien <raph@acm.org>
  23  *          Alexander Larsson <alla@lysator.liu.se>
  24  */
  25
  26 #ifndef __ART_RENDER_GRADIENT_H__
  27 #define __ART_RENDER_GRADIENT_H__
  28
  29 #ifdef LIBART_COMPILATION
  30 #include "art_filterlevel.h"
  31 #include "art_render.h"
  32 #else
  33 #include "art_filterlevel.h"
  34 #include "art_render.h"
  35 #endif
  36
  37 #ifdef __cplusplus
  38 extern "C" {
  39 #endif /* __cplusplus */
  40
  41 typedef struct _ArtGradientLinear ArtGradientLinear;
  42 typedef struct _ArtGradientRadial ArtGradientRadial;
  43 typedef struct _ArtGradientStop ArtGradientStop;
  44
  45 typedef enum {
  46   ART_GRADIENT_PAD,
  47   ART_GRADIENT_REFLECT,
  48   ART_GRADIENT_REPEAT
  49 } ArtGradientSpread;
  50
  51 struct _ArtGradientLinear {
  52   double a;
  53   double b;
  54   double c;
  55   ArtGradientSpread spread;
  56   int n_stops;
  57   ArtGradientStop *stops;
  58 };
  59
  60 struct _ArtGradientRadial {
  61   double affine[6]; /* transforms user coordinates to unit circle */
  62   double fx, fy;    /* focal point in unit circle coords */
  63   int n_stops;
  64   ArtGradientStop *stops;
  65 };
  66
  67 struct _ArtGradientStop {
  68   double offset;
  69   ArtPixMaxDepth color[ART_MAX_CHAN + 1];
  70 };
  71
  72 void
  73 art_render_gradient_linear (ArtRender *render,
  74                             const ArtGradientLinear *gradient,
  75                             ArtFilterLevel level);
  76
  77 void
  78 art_render_gradient_radial (ArtRender *render,
  79                             const ArtGradientRadial *gradient,
  80                             ArtFilterLevel level);
  81
  82 #ifdef __cplusplus
  83 }
  84 #endif /* __cplusplus */
  85
  86 #endif /* __ART_RENDER_GRADIENT_H__ */