| 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 */ |