miline.h (5763B)
1 2 /* 3 4 Copyright 1994, 1998 The Open Group 5 6 Permission to use, copy, modify, distribute, and sell this software and its 7 documentation for any purpose is hereby granted without fee, provided that 8 the above copyright notice appear in all copies and that both that 9 copyright notice and this permission notice appear in supporting 10 documentation. 11 12 The above copyright notice and this permission notice shall be included in 13 all copies or substantial portions of the Software. 14 15 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 18 OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN 19 AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 20 CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 21 22 Except as contained in this notice, the name of The Open Group shall not be 23 used in advertising or otherwise to promote the sale, use or other dealings 24 in this Software without prior written authorization from The Open Group. 25 26 */ 27 28 #ifndef MILINE_H 29 30 #include "screenint.h" 31 #include "privates.h" 32 33 /* 34 * Public definitions used for configuring basic pixelization aspects 35 * of the sample implementation line-drawing routines provided in 36 * {mfb,mi,cfb*} at run-time. 37 */ 38 39 #define XDECREASING 4 40 #define YDECREASING 2 41 #define YMAJOR 1 42 43 #define OCTANT1 (1 << (YDECREASING)) 44 #define OCTANT2 (1 << (YDECREASING|YMAJOR)) 45 #define OCTANT3 (1 << (XDECREASING|YDECREASING|YMAJOR)) 46 #define OCTANT4 (1 << (XDECREASING|YDECREASING)) 47 #define OCTANT5 (1 << (XDECREASING)) 48 #define OCTANT6 (1 << (XDECREASING|YMAJOR)) 49 #define OCTANT7 (1 << (YMAJOR)) 50 #define OCTANT8 (1 << (0)) 51 52 #define XMAJOROCTANTS (OCTANT1 | OCTANT4 | OCTANT5 | OCTANT8) 53 54 #define DEFAULTZEROLINEBIAS (OCTANT2 | OCTANT3 | OCTANT4 | OCTANT5) 55 56 /* 57 * Devices can configure the rendering of routines in mi, mfb, and cfb* 58 * by specifying a thin line bias to be applied to a particular screen 59 * using the following function. The bias parameter is an OR'ing of 60 * the appropriate OCTANT constants defined above to indicate which 61 * octants to bias a line to prefer an axial step when the Bresenham 62 * error term is exactly zero. The octants are mapped as follows: 63 * 64 * \ | / 65 * \ 3 | 2 / 66 * \ | / 67 * 4 \ | / 1 68 * \|/ 69 * ----------- 70 * /|\ 71 * 5 / | \ 8 72 * / | \ 73 * / 6 | 7 \ 74 * / | \ 75 * 76 * For more information, see "Ambiguities in Incremental Line Rastering," 77 * Jack E. Bresenham, IEEE CG&A, May 1987. 78 */ 79 80 extern _X_EXPORT void miSetZeroLineBias(ScreenPtr /* pScreen */ , 81 unsigned int /* bias */ 82 ); 83 84 /* 85 * Private definitions needed for drawing thin (zero width) lines 86 * Used by the mi, mfb, and all cfb* components. 87 */ 88 89 #define X_AXIS 0 90 #define Y_AXIS 1 91 92 #define OUT_LEFT 0x08 93 #define OUT_RIGHT 0x04 94 #define OUT_ABOVE 0x02 95 #define OUT_BELOW 0x01 96 97 #define OUTCODES(_result, _x, _y, _pbox) \ 98 if ( (_x) < (_pbox)->x1) (_result) |= OUT_LEFT; \ 99 else if ( (_x) >= (_pbox)->x2) (_result) |= OUT_RIGHT; \ 100 if ( (_y) < (_pbox)->y1) (_result) |= OUT_ABOVE; \ 101 else if ( (_y) >= (_pbox)->y2) (_result) |= OUT_BELOW; 102 103 #define MIOUTCODES(outcode, x, y, xmin, ymin, xmax, ymax) \ 104 {\ 105 if (x < xmin) outcode |= OUT_LEFT;\ 106 if (x > xmax) outcode |= OUT_RIGHT;\ 107 if (y < ymin) outcode |= OUT_ABOVE;\ 108 if (y > ymax) outcode |= OUT_BELOW;\ 109 } 110 111 #define SWAPINT(i, j) \ 112 { int _t = i; i = j; j = _t; } 113 114 #define SWAPPT(i, j) \ 115 { DDXPointRec _t; _t = i; i = j; j = _t; } 116 117 #define SWAPINT_PAIR(x1, y1, x2, y2)\ 118 { int t = x1; x1 = x2; x2 = t;\ 119 t = y1; y1 = y2; y2 = t;\ 120 } 121 122 #define miGetZeroLineBias(_pScreen) ((unsigned long) (unsigned long*)\ 123 dixLookupPrivate(&(_pScreen)->devPrivates, miZeroLineScreenKey)) 124 125 #define CalcLineDeltas(_x1,_y1,_x2,_y2,_adx,_ady,_sx,_sy,_SX,_SY,_octant) \ 126 (_octant) = 0; \ 127 (_sx) = (_SX); \ 128 if (((_adx) = (_x2) - (_x1)) < 0) { \ 129 (_adx) = -(_adx); \ 130 (_sx = -(_sx)); \ 131 (_octant) |= XDECREASING; \ 132 } \ 133 (_sy) = (_SY); \ 134 if (((_ady) = (_y2) - (_y1)) < 0) { \ 135 (_ady) = -(_ady); \ 136 (_sy = -(_sy)); \ 137 (_octant) |= YDECREASING; \ 138 } 139 140 #define SetYMajorOctant(_octant) ((_octant) |= YMAJOR) 141 142 #define FIXUP_ERROR(_e, _octant, _bias) \ 143 (_e) -= (((_bias) >> (_octant)) & 1) 144 145 #define IsXMajorOctant(_octant) (!((_octant) & YMAJOR)) 146 #define IsYMajorOctant(_octant) ((_octant) & YMAJOR) 147 #define IsXDecreasingOctant(_octant) ((_octant) & XDECREASING) 148 #define IsYDecreasingOctant(_octant) ((_octant) & YDECREASING) 149 150 extern _X_EXPORT DevPrivateKeyRec miZeroLineScreenKeyRec; 151 152 #define miZeroLineScreenKey (&miZeroLineScreenKeyRec) 153 154 extern _X_EXPORT int miZeroClipLine(int /*xmin */ , 155 int /*ymin */ , 156 int /*xmax */ , 157 int /*ymax */ , 158 int * /*new_x1 */ , 159 int * /*new_y1 */ , 160 int * /*new_x2 */ , 161 int * /*new_y2 */ , 162 unsigned int /*adx */ , 163 unsigned int /*ady */ , 164 int * /*pt1_clipped */ , 165 int * /*pt2_clipped */ , 166 int /*octant */ , 167 unsigned int /*bias */ , 168 int /*oc1 */ , 169 int /*oc2 */ 170 ); 171 172 #endif /* MILINE_H */