New implementation of antialiased lines. Mesa should now pass the remaining

GL conformance tests for AA lines (but not tried yet).
TODO: improve code sharing with the AA triangle code.

1 files changed, 322 insertions, 0 deletions

diff --git a/src/mesa/swrast/s_aalinetemp.h b/src/mesa/swrast/s_aalinetemp.h
new file mode 100644
index 0000000000..ee414aae59
--- /dev/null
+++ b/src/mesa/swrast/s_aalinetemp.h
@@ -0,0 +1,322 @@
+/* $Id: s_aalinetemp.h,v 1.1 2000/11/05 23:15:16 brianp Exp $ */
+
+/*
+ * Mesa 3-D graphics library
+ * Version:  3.5
+ * 
+ * Copyright (C) 1999-2000  Brian Paul   All Rights Reserved.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+
+/*
+ * Antialiased line template.
+ */
+
+
+/*
+ * Function to render each fragment in the AA line.
+ */
+static void
+NAME(plot)(GLcontext *ctx, const struct LineInfo *line,
+           struct pixel_buffer *pb, int ix, int iy)
+{
+   const GLfloat fx = (GLfloat) ix;
+   const GLfloat fy = (GLfloat) iy;
+   const GLfloat coverage = compute_coveragef(line, ix, iy);
+   GLdepth z;
+   GLfloat fog;
+   GLchan red, green, blue, alpha;
+   GLint frac, indx, index;
+   GLchan specRed, specGreen, specBlue;
+   GLfloat tex[MAX_TEXTURE_UNITS][4], lambda[MAX_TEXTURE_UNITS];
+
+   if (coverage == 0.0)
+      return;
+
+   /*
+    * Compute Z, color, texture coords, fog for the fragment by
+    * solving the plane equations at (ix,iy).
+    */
+#ifdef DO_Z
+   z = (GLdepth) solve_plane(fx, fy, line->zPlane);
+#else
+   z = 0.0;
+#endif
+#ifdef DO_FOG
+   fog = solve_plane(fx, fy, line->fPlane);
+#else
+   fog = 0.0;
+#endif
+#ifdef DO_RGBA
+   red   = solve_plane_chan(fx, fy, line->rPlane);
+   green = solve_plane_chan(fx, fy, line->gPlane);
+   blue  = solve_plane_chan(fx, fy, line->bPlane);
+   alpha = (GLchan) (solve_plane_chan(fx, fy, line->aPlane) * coverage);;
+#else
+   (void) red;
+   (void) green;
+   (void) blue;
+   (void) alpha;
+#endif
+#ifdef DO_INDEX
+   frac = (GLint) (15.0 * coverage);
+   indx = (GLint) solve_plane(fx, fy, line->iPlane);
+   index = (indx & ~0xf) | frac;
+#else
+   (void) frac;
+   (void) indx;
+   (void) index;
+#endif
+#ifdef DO_SPEC
+   specRed   = solve_plane_chan(fx, fy, line->srPlane);
+   specGreen = solve_plane_chan(fx, fy, line->sgPlane);
+   specBlue  = solve_plane_chan(fx, fy, line->sbPlane);
+#else
+   (void) specRed;
+   (void) specGreen;
+   (void) specBlue;
+#endif
+#ifdef DO_TEX
+   {
+      GLfloat invQ = solve_plane_recip(fx, fy, line->vPlane[0]);
+      tex[0][0] = solve_plane(fx, fy, line->sPlane[0]) * invQ;
+      tex[0][1] = solve_plane(fx, fy, line->tPlane[0]) * invQ;
+      tex[0][2] = solve_plane(fx, fy, line->uPlane[0]) * invQ;
+      lambda[0] = compute_lambda(line->sPlane[0], line->tPlane[0], invQ,
+                                 line->texWidth[0], line->texHeight[0]);
+   }
+#elif defined(DO_MULTITEX)
+   {
+      GLuint unit;
+      for (unit = 0; unit < ctx->Const.MaxTextureUnits; unit++) {
+         if (ctx->Texture.Unit[unit]._ReallyEnabled) {
+            GLfloat invQ = solve_plane_recip(fx, fy, line->vPlane[unit]);
+            tex[unit][0] = solve_plane(fx, fy, line->sPlane[unit]) * invQ;
+            tex[unit][1] = solve_plane(fx, fy, line->tPlane[unit]) * invQ;
+            tex[unit][2] = solve_plane(fx, fy, line->uPlane[unit]) * invQ;
+            lambda[unit] = compute_lambda(line->sPlane[unit],
+                                          line->tPlane[unit], invQ,
+                                          line->texWidth[unit], line->texHeight[unit]);
+         }
+      }
+   }
+#else
+   (void) tex[0][0];
+   (void) lambda[0];
+#endif
+
+
+#if defined(DO_MULTITEX)
+#if defined(DO_SPEC)
+   PB_WRITE_MULTITEX_SPEC_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha,
+                                specRed, specGreen, specBlue, tex);
+#else
+   PB_WRITE_MULTITEX_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha, texcoords);
+#endif
+#elif defined(DO_TEX)
+   PB_WRITE_TEX_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha,
+                      tex[0][0], tex[0][1], tex[0][2]);
+#elif defined(DO_RGBA)
+   PB_WRITE_RGBA_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha);
+#elif defined(DO_INDEX)
+   PB_WRITE_CI_PIXEL(pb, ix, iy, z, fog, index);
+#endif
+
+   PB_CHECK_FLUSH(ctx, pb);
+}
+
+
+
+/*
+ * Line setup
+ */
+static void
+NAME(line)(GLcontext *ctx, SWvertex *v0, SWvertex *v1)
+{
+   SWcontext *swrast = SWRAST_CONTEXT(ctx);
+   struct pixel_buffer *pb = SWRAST_CONTEXT(ctx)->PB;
+   GLfloat tStart, tEnd;   /* segment start, end along line length */
+   GLboolean inSegment;
+   GLint iLen, i;
+
+   /* Init the LineInfo struct */
+   struct LineInfo line;
+   line.x0 = v0->win[0];
+   line.y0 = v0->win[1];
+   line.x1 = v1->win[0];
+   line.y1 = v1->win[1];
+   line.dx = line.x1 - line.x0;
+   line.dy = line.y1 - line.y0;
+   line.len = sqrt(line.dx * line.dx + line.dy * line.dy);
+   line.halfWidth = 0.5F * ctx->Line.Width;
+   line.xAdj = line.dx / line.len * line.halfWidth;
+   line.yAdj = line.dy / line.len * line.halfWidth;
+
+#ifdef DO_Z
+   compute_plane(line.x0, line.y0, line.x1, line.y1,
+                 v0->win[2], v1->win[2], line.zPlane);
+#endif
+#ifdef DO_FOG
+   compute_plane(line.x0, line.y0, line.x1, line.y1,
+                 v0->fog, v1->fog, line.fPlane);
+#endif
+#ifdef DO_RGBA
+   if (ctx->Light.ShadeModel == GL_SMOOTH) {
+      compute_plane(line.x0, line.y0, line.x1, line.y1,
+                    v0->color[RCOMP], v1->color[RCOMP], line.rPlane);
+      compute_plane(line.x0, line.y0, line.x1, line.y1,
+                    v0->color[GCOMP], v1->color[GCOMP], line.gPlane);
+      compute_plane(line.x0, line.y0, line.x1, line.y1,
+                    v0->color[BCOMP], v1->color[BCOMP], line.bPlane);
+      compute_plane(line.x0, line.y0, line.x1, line.y1,
+                    v0->color[ACOMP], v1->color[ACOMP], line.aPlane);
+   }
+   else {
+      constant_plane(v0->color[RCOMP], line.rPlane);
+      constant_plane(v0->color[GCOMP], line.gPlane);
+      constant_plane(v0->color[BCOMP], line.bPlane);
+      constant_plane(v0->color[ACOMP], line.aPlane);
+   }
+#endif
+#ifdef DO_SPEC
+   if (ctx->Light.ShadeModel == GL_SMOOTH) {
+      compute_plane(line.x0, line.y0, line.x1, line.y1,
+                    v0->specular[RCOMP], v1->specular[RCOMP], line.srPlane);
+      compute_plane(line.x0, line.y0, line.x1, line.y1,
+                    v0->specular[GCOMP], v1->specular[GCOMP], line.sgPlane);
+      compute_plane(line.x0, line.y0, line.x1, line.y1,
+                    v0->specular[BCOMP], v1->specular[BCOMP], line.sbPlane);
+   }
+   else {
+      constant_plane(v0->specular[RCOMP], line.srPlane);
+      constant_plane(v0->specular[GCOMP], line.sgPlane);
+      constant_plane(v0->specular[BCOMP], line.sbPlane);
+   }
+#endif
+#ifdef DO_INDEX
+   if (ctx->Light.ShadeModel == GL_SMOOTH) {
+      compute_plane(line.x0, line.y0, line.x1, line.y1,
+                    v0->index, v1->index, line.iPlane);
+   }
+   else {
+      constant_plane(v0->index, line.iPlane);
+   }
+#endif
+#ifdef DO_TEX
+   {
+      const struct gl_texture_object *obj = ctx->Texture.Unit[0]._Current;
+      const struct gl_texture_image *texImage = obj->Image[obj->BaseLevel];
+      const GLfloat invW0 = v0->win[3];
+      const GLfloat invW1 = v1->win[3];
+      const GLfloat s0 = v0->texcoord[0][0] * invW0;
+      const GLfloat s1 = v1->texcoord[0][0] * invW1;
+      const GLfloat t0 = v0->texcoord[0][1] * invW0;
+      const GLfloat t1 = v1->texcoord[0][1] * invW0;
+      const GLfloat r0 = v0->texcoord[0][2] * invW0;
+      const GLfloat r1 = v1->texcoord[0][2] * invW0;
+      const GLfloat q0 = v0->texcoord[0][3] * invW0;
+      const GLfloat q1 = v1->texcoord[0][3] * invW0;
+      compute_plane(line.x0, line.y0, line.x1, line.y1, s0, s1, line.sPlane[0]);
+      compute_plane(line.x0, line.y0, line.x1, line.y1, t0, t1, line.tPlane[0]);
+      compute_plane(line.x0, line.y0, line.x1, line.y1, r0, r1, line.uPlane[0]);
+      compute_plane(line.x0, line.y0, line.x1, line.y1, q0, q1, line.vPlane[0]);
+      line.texWidth[0] = (GLfloat) texImage->Width;
+      line.texHeight[0] = (GLfloat) texImage->Height;
+   }
+#elif defined(DO_MULITEX)
+   {
+      GLuint u;
+      for (u = 0; u < ctx->Const.MaxTextureUnits; u++) {
+         if (ctx->Texture.Unit[u].ReallyEnabled) {
+            const struct gl_texture_object *obj = ctx->Texture.Unit[u].Current;
+            const struct gl_texture_image *texImage = obj->Image[obj->BaseLevel];
+            const GLfloat invW0 = v0->win[3];
+            const GLfloat invW1 = v1->win[3];
+            GLfloat (*texCoord)[4] = VB->TexCoordPtr[u]->data;
+            const GLfloat s0 = v0->texcoord[u][0] * invW0;
+            const GLfloat s1 = v1->texcoord[u][0] * invW1;
+            const GLfloat t0 = v0->texcoord[u][1] * invW0;
+            const GLfloat t1 = v1->texcoord[u][1] * invW0;
+            const GLfloat r0 = v0->texcoord[u][2] * invW0;
+            const GLfloat r1 = v1->texcoord[u][2] * invW0;
+            const GLfloat q0 = v0->texcoord[u][3] * invW0;
+            const GLfloat q1 = v1->texcoord[u][3] * invW0;
+            compute_plane(line.x0, line.y0, line.x1, line.y1, s0, s1, line.sPlane[u]);
+            compute_plane(line.x0, line.y0, line.x1, line.y1, t0, t1, line.tPlane[u]);
+            compute_plane(line.x0, line.y0, line.x1, line.y1, u0, u1, line.uPlane[u]);
+            compute_plane(line.x0, line.y0, line.x1, line.y1, v0, v1, line.vPlane[u]);
+            line.texWidth[u]  = (GLfloat) texImage->Width;
+            line.texHeight[u] = (GLfloat) texImage->Height;
+         }
+      }
+   }
+#endif
+
+   tStart = tEnd = 0.0;
+   inSegment = GL_FALSE;
+   iLen = (GLint) line.len;
+
+   if (ctx->Line.StippleFlag) {
+      for (i = 0; i < iLen; i++) {
+         const GLuint bit = (swrast->StippleCounter / ctx->Line.StippleFactor) & 0xf;
+         if ((1 << bit) & ctx->Line.StipplePattern) {
+            /* stipple bit is on */
+            const GLfloat t = (GLfloat) i / (GLfloat) line.len;
+            if (!inSegment) {
+               /* start new segment */
+               inSegment = GL_TRUE;
+               tStart = t;
+            }
+            else {
+               /* still in the segment, extend it */
+               tEnd = t;
+            }
+         }
+         else {
+            /* stipple bit is off */
+            if (inSegment && (tEnd > tStart)) {
+               /* draw the segment */
+               segment(ctx, &line, NAME(plot), pb, tStart, tEnd);
+               inSegment = GL_FALSE;
+            }
+            else {
+               /* still between segments, do nothing */
+            }
+         }
+         swrast->StippleCounter++;
+      }
+   }
+   else {
+      /* non-stippled */
+      segment(ctx, &line, NAME(plot), pb, 0.0, 1.0);
+   }
+}
+
+
+
+
+#undef DO_Z
+#undef DO_FOG
+#undef DO_RGBA
+#undef DO_INDEX
+#undef DO_SPEC
+#undef DO_TEX
+#undef DO_MULTITEX
+#undef NAME