2  * Mesa 3-D graphics library
4  * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
49    const GLfloat px = v1[0] - v0[0];  in compute_plane()
50    const GLfloat py = v1[1] - v0[1];  in compute_plane()
51    const GLfloat pz = z1 - z0;  in compute_plane()
53    const GLfloat qx = v2[0] - v0[0];  in compute_plane()
54    const GLfloat qy = v2[1] - v0[1];  in compute_plane()
55    const GLfloat qz = z2 - z0;  in compute_plane()
58    const GLfloat a = py * qz - pz * qy;  in compute_plane()
59    const GLfloat b = pz * qx - px * qz;  in compute_plane()
60    const GLfloat c = px * qy - py * qx;  in compute_plane()
65       which is equal to "-d" below. */  in compute_plane()
66    const GLfloat d = -(a * v0[0] + b * v0[1] + c * z0);  in compute_plane()
83    plane[2] = -1.0;  in constant_plane()
91    PLANE[2] = -1.0F;			\
104    return (plane[3] + plane[0] * x + plane[1] * y) / -plane[2];  in solve_plane()
109    ((PLANE[3] + PLANE[0] * (X) + PLANE[1] * (Y)) / -PLANE[2])
118    const GLfloat z = (plane[3] + plane[0] * x + plane[1] * y) / -plane[2];  in solve_plane_chan()
134    return -plane[0] / plane[2];  in plane_dx()
140    return -plane[1] / plane[2];  in plane_dy()
147  * Vertices MUST be specified in counter-clockwise order.
154    /* Given a position [0,3]x[0,3] return the sub-pixel sample position.  in compute_coveragef()
157     * Jitter sample positions -  in compute_coveragef()
158     * - average should be .5 in x & y for each column  in compute_coveragef()
159     * - each of the 16 rows and columns should be used once  in compute_coveragef()
160     * - the rectangle formed by the first four points  in compute_coveragef()
162     * - the distrubition should be fairly even in any given direction  in compute_coveragef()
193    const GLfloat dx0 = v1[0] - v0[0];  in compute_coveragef()
194    const GLfloat dy0 = v1[1] - v0[1];  in compute_coveragef()
195    const GLfloat dx1 = v2[0] - v1[0];  in compute_coveragef()
196    const GLfloat dy1 = v2[1] - v1[1];  in compute_coveragef()
197    const GLfloat dx2 = v0[0] - v2[0];  in compute_coveragef()
198    const GLfloat dy2 = v0[1] - v2[1];  in compute_coveragef()
202    assert(dx0 * dy1 - dx1 * dy0 >= 0.0); /* area >= 0.0 */  in compute_coveragef()
207       /* cross product determines if sample is inside or outside each edge */  in compute_coveragef()
208       GLfloat cross = (dx0 * (sy - v0[1]) - dy0 * (sx - v0[0]));  in compute_coveragef()  local
209       /* Check if the sample is exactly on an edge.  If so, let cross be a  in compute_coveragef()
212       if (cross == 0.0F)  in compute_coveragef()
213          cross = dx0 + dy0;  in compute_coveragef()
214       if (cross < 0.0F) {  in compute_coveragef()
216          insideCount -= 1.0F;  in compute_coveragef()
221          cross = (dx1 * (sy - v1[1]) - dy1 * (sx - v1[0]));  in compute_coveragef()
222          if (cross == 0.0F)  in compute_coveragef()
223             cross = dx1 + dy1;  in compute_coveragef()
224          if (cross < 0.0F) {  in compute_coveragef()
226             insideCount -= 1.0F;  in compute_coveragef()
231             cross = (dx2 * (sy - v2[1]) -  dy2 * (sx - v2[0]));  in compute_coveragef()
232             if (cross == 0.0F)  in compute_coveragef()
233                cross = dx2 + dy2;  in compute_coveragef()
234             if (cross < 0.0F) {  in compute_coveragef()
236                insideCount -= 1.0F;  in compute_coveragef()
275  * Examine GL state and set swrast->Triangle to an
283    assert(ctx->Polygon.SmoothFlag);  in _swrast_set_aa_triangle_function()
285    if (ctx->Texture._EnabledCoordUnits != 0  in _swrast_set_aa_triangle_function()
287        || swrast->_FogEnabled  in _swrast_set_aa_triangle_function()
289       SWRAST_CONTEXT(ctx)->Triangle = general_aa_tri;  in _swrast_set_aa_triangle_function()
292       SWRAST_CONTEXT(ctx)->Triangle = rgba_aa_tri;  in _swrast_set_aa_triangle_function()
295    assert(SWRAST_CONTEXT(ctx)->Triangle);  in _swrast_set_aa_triangle_function()