progs/openvg/trivial/stroke.c

   1 #include "eglcommon.h"
   2
   3 #include <VG/openvg.h>
   4 #include <X11/keysym.h>
   5 #include <stdio.h>
   6
   7 const VGfloat white_color[4] = {1.0, 1.0, 1.0, 1.0};
   8 const VGfloat color[4] = {0.4, 0.1, 1.0, 1.0};
   9
  10 VGPath path;
  11 VGPaint fill;
  12
  13 VGint cap_style = VG_CAP_BUTT;
  14 VGint join_style = VG_JOIN_MITER;
  15
  16 static void
  17 init(void)
  18 {
  19 #if 0
  20    static const VGubyte cmds[] = {VG_MOVE_TO_ABS,
  21                                   VG_CUBIC_TO_ABS,
  22    };
  23    static const VGfloat coords[]   = {30, 30, 264, 0, 0, 264, 234, 234
  24    };
  25 #else
  26    static const VGubyte cmds[] = {VG_MOVE_TO_ABS,
  27                                   VG_LINE_TO_ABS,
  28                                   VG_LINE_TO_ABS
  29    };
  30    static const VGfloat coords[]   = {30, 30, 202, 30, 150, 224
  31    };
  32 #endif
  33    VGfloat dash_pattern[2] = { 20.f, 20.f };
  34    path = vgCreatePath(VG_PATH_FORMAT_STANDARD, VG_PATH_DATATYPE_F, 1, 0, 0, 0,
  35                        VG_PATH_CAPABILITY_APPEND_TO);
  36    vgAppendPathData(path, 3, cmds, coords);
  37
  38    fill = vgCreatePaint();
  39    vgSetParameterfv(fill, VG_PAINT_COLOR, 4, color);
  40    vgSetPaint(fill, VG_FILL_PATH);
  41
  42    vgSetfv(VG_CLEAR_COLOR, 4, white_color);
  43    vgSetf(VG_STROKE_LINE_WIDTH, 20);
  44    vgSeti(VG_STROKE_CAP_STYLE, cap_style);
  45    vgSeti(VG_STROKE_JOIN_STYLE, join_style);
  46    vgSetfv(VG_STROKE_DASH_PATTERN, 2, dash_pattern);
  47    vgSetf(VG_STROKE_DASH_PHASE, 0.0f);
  48 }
  49
  50 /* new window size or exposure */
  51 static void
  52 reshape(int w, int h)
  53 {
  54    vgLoadIdentity();
  55 }
  56
  57 static void
  58 draw(void)
  59 {
  60    vgClear(0, 0, window_width(), window_height());
  61    vgDrawPath(path, VG_STROKE_PATH);
  62
  63    vgFlush();
  64 }
  65
  66 static int  key_press(unsigned key)
  67 {
  68     switch(key) {
  69     case XK_c:
  70     case XK_C:
  71         ++cap_style;
  72         if (cap_style > VG_CAP_SQUARE)
  73             cap_style = VG_CAP_BUTT;
  74         switch(cap_style) {
  75         case VG_CAP_BUTT:
  76             fprintf(stderr, "Cap style 'butt'\n");
  77             break;
  78         case VG_CAP_ROUND:
  79             fprintf(stderr, "Cap style 'round'\n");
  80             break;
  81         case VG_CAP_SQUARE:
  82             fprintf(stderr, "Cap style 'square'\n");
  83             break;
  84         }
  85         vgSeti(VG_STROKE_CAP_STYLE, cap_style);
  86         break;
  87     case XK_j:
  88     case XK_J:
  89         ++join_style;
  90         if (join_style > VG_JOIN_BEVEL)
  91             join_style = VG_JOIN_MITER;
  92         switch(join_style) {
  93         case VG_JOIN_MITER:
  94             fprintf(stderr, "Join style 'miter'\n");
  95             break;
  96         case VG_JOIN_ROUND:
  97             fprintf(stderr, "Join style 'round'\n");
  98             break;
  99         case VG_JOIN_BEVEL:
 100             fprintf(stderr, "Join style 'bevel'\n");
 101             break;
 102         }
 103         vgSeti(VG_STROKE_JOIN_STYLE, join_style);
 104         break;
 105     default:
 106         break;
 107     }
 108
 109     return VG_TRUE;
 110 }
 111
 112 int main(int argc, char **argv)
 113 {
 114    return run(argc, argv, init, reshape,
 115               draw, key_press);
 116 }