| /* |
| * Mesa 3-D graphics library |
| * Version: 7.1 |
| * |
| * Copyright (C) 1999-2007 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. |
| * \param ix - integer fragment window X coordiante |
| * \param iy - integer fragment window Y coordiante |
| */ |
| static void |
| NAME(plot)(GLcontext *ctx, struct LineInfo *line, int ix, int iy) |
| { |
| const SWcontext *swrast = SWRAST_CONTEXT(ctx); |
| const GLfloat fx = (GLfloat) ix; |
| const GLfloat fy = (GLfloat) iy; |
| #ifdef DO_INDEX |
| const GLfloat coverage = compute_coveragei(line, ix, iy); |
| #else |
| const GLfloat coverage = compute_coveragef(line, ix, iy); |
| #endif |
| const GLuint i = line->span.end; |
| |
| (void) swrast; |
| |
| if (coverage == 0.0) |
| return; |
| |
| line->span.end++; |
| line->span.array->coverage[i] = coverage; |
| line->span.array->x[i] = ix; |
| line->span.array->y[i] = iy; |
| |
| /* |
| * Compute Z, color, texture coords, fog for the fragment by |
| * solving the plane equations at (ix,iy). |
| */ |
| #ifdef DO_Z |
| line->span.array->z[i] = (GLuint) solve_plane(fx, fy, line->zPlane); |
| #endif |
| #ifdef DO_RGBA |
| line->span.array->rgba[i][RCOMP] = solve_plane_chan(fx, fy, line->rPlane); |
| line->span.array->rgba[i][GCOMP] = solve_plane_chan(fx, fy, line->gPlane); |
| line->span.array->rgba[i][BCOMP] = solve_plane_chan(fx, fy, line->bPlane); |
| line->span.array->rgba[i][ACOMP] = solve_plane_chan(fx, fy, line->aPlane); |
| #endif |
| #ifdef DO_INDEX |
| line->span.array->index[i] = (GLint) solve_plane(fx, fy, line->iPlane); |
| #endif |
| #if defined(DO_ATTRIBS) |
| ATTRIB_LOOP_BEGIN |
| GLfloat (*attribArray)[4] = line->span.array->attribs[attr]; |
| if (attr >= FRAG_ATTRIB_TEX0 && attr < FRAG_ATTRIB_VAR0 |
| && !ctx->FragmentProgram._Active) { |
| /* texcoord w/ divide by Q */ |
| const GLuint unit = attr - FRAG_ATTRIB_TEX0; |
| const GLfloat invQ = solve_plane_recip(fx, fy, line->attrPlane[attr][3]); |
| GLuint c; |
| for (c = 0; c < 3; c++) { |
| attribArray[i][c] = solve_plane(fx, fy, line->attrPlane[attr][c]) * invQ; |
| } |
| line->span.array->lambda[unit][i] |
| = compute_lambda(line->attrPlane[attr][0], |
| line->attrPlane[attr][1], invQ, |
| line->texWidth[attr], line->texHeight[attr]); |
| } |
| else { |
| /* non-texture attrib */ |
| const GLfloat invW = solve_plane_recip(fx, fy, line->wPlane); |
| GLuint c; |
| for (c = 0; c < 4; c++) { |
| attribArray[i][c] = solve_plane(fx, fy, line->attrPlane[attr][c]) * invW; |
| } |
| } |
| ATTRIB_LOOP_END |
| #endif |
| |
| if (line->span.end == MAX_WIDTH) { |
| #if defined(DO_RGBA) |
| _swrast_write_rgba_span(ctx, &(line->span)); |
| #else |
| _swrast_write_index_span(ctx, &(line->span)); |
| #endif |
| line->span.end = 0; /* reset counter */ |
| } |
| } |
| |
| |
| |
| /* |
| * Line setup |
| */ |
| static void |
| NAME(line)(GLcontext *ctx, const SWvertex *v0, const SWvertex *v1) |
| { |
| SWcontext *swrast = SWRAST_CONTEXT(ctx); |
| GLfloat tStart, tEnd; /* segment start, end along line length */ |
| GLboolean inSegment; |
| GLint iLen, i; |
| |
| /* Init the LineInfo struct */ |
| struct LineInfo line; |
| line.x0 = v0->attrib[FRAG_ATTRIB_WPOS][0]; |
| line.y0 = v0->attrib[FRAG_ATTRIB_WPOS][1]; |
| line.x1 = v1->attrib[FRAG_ATTRIB_WPOS][0]; |
| line.y1 = v1->attrib[FRAG_ATTRIB_WPOS][1]; |
| line.dx = line.x1 - line.x0; |
| line.dy = line.y1 - line.y0; |
| line.len = SQRTF(line.dx * line.dx + line.dy * line.dy); |
| line.halfWidth = 0.5F * CLAMP(ctx->Line.Width, |
| ctx->Const.MinLineWidthAA, |
| ctx->Const.MaxLineWidthAA); |
| |
| if (line.len == 0.0 || IS_INF_OR_NAN(line.len)) |
| return; |
| |
| INIT_SPAN(line.span, GL_LINE); |
| line.span.arrayMask = SPAN_XY | SPAN_COVERAGE; |
| line.span.facing = swrast->PointLineFacing; |
| line.xAdj = line.dx / line.len * line.halfWidth; |
| line.yAdj = line.dy / line.len * line.halfWidth; |
| |
| #ifdef DO_Z |
| line.span.arrayMask |= SPAN_Z; |
| compute_plane(line.x0, line.y0, line.x1, line.y1, |
| v0->attrib[FRAG_ATTRIB_WPOS][2], v1->attrib[FRAG_ATTRIB_WPOS][2], line.zPlane); |
| #endif |
| #ifdef DO_RGBA |
| line.span.arrayMask |= SPAN_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(v1->color[RCOMP], line.rPlane); |
| constant_plane(v1->color[GCOMP], line.gPlane); |
| constant_plane(v1->color[BCOMP], line.bPlane); |
| constant_plane(v1->color[ACOMP], line.aPlane); |
| } |
| #endif |
| #ifdef DO_INDEX |
| line.span.arrayMask |= SPAN_INDEX; |
| if (ctx->Light.ShadeModel == GL_SMOOTH) { |
| compute_plane(line.x0, line.y0, line.x1, line.y1, |
| v0->attrib[FRAG_ATTRIB_CI][0], |
| v1->attrib[FRAG_ATTRIB_CI][0], line.iPlane); |
| } |
| else { |
| constant_plane(v1->attrib[FRAG_ATTRIB_CI][0], line.iPlane); |
| } |
| #endif |
| #if defined(DO_ATTRIBS) |
| { |
| const GLfloat invW0 = v0->attrib[FRAG_ATTRIB_WPOS][3]; |
| const GLfloat invW1 = v1->attrib[FRAG_ATTRIB_WPOS][3]; |
| line.span.arrayMask |= SPAN_LAMBDA; |
| compute_plane(line.x0, line.y0, line.x1, line.y1, invW0, invW1, line.wPlane); |
| ATTRIB_LOOP_BEGIN |
| GLuint c; |
| if (swrast->_InterpMode[attr] == GL_FLAT) { |
| for (c = 0; c < 4; c++) { |
| constant_plane(v1->attrib[attr][c], line.attrPlane[attr][c]); |
| } |
| } |
| else { |
| for (c = 0; c < 4; c++) { |
| const GLfloat a0 = v0->attrib[attr][c] * invW0; |
| const GLfloat a1 = v1->attrib[attr][c] * invW1; |
| compute_plane(line.x0, line.y0, line.x1, line.y1, a0, a1, |
| line.attrPlane[attr][c]); |
| } |
| } |
| line.span.arrayAttribs |= (1 << attr); |
| if (attr >= FRAG_ATTRIB_TEX0 && attr < FRAG_ATTRIB_VAR0) { |
| const GLuint u = attr - FRAG_ATTRIB_TEX0; |
| const struct gl_texture_object *obj = ctx->Texture.Unit[u]._Current; |
| const struct gl_texture_image *texImage = obj->Image[0][obj->BaseLevel]; |
| line.texWidth[attr] = (GLfloat) texImage->Width; |
| line.texHeight[attr] = (GLfloat) texImage->Height; |
| } |
| ATTRIB_LOOP_END |
| } |
| #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), tStart, tEnd); |
| inSegment = GL_FALSE; |
| } |
| else { |
| /* still between segments, do nothing */ |
| } |
| } |
| swrast->StippleCounter++; |
| } |
| |
| if (inSegment) { |
| /* draw the final segment of the line */ |
| segment(ctx, &line, NAME(plot), tStart, 1.0F); |
| } |
| } |
| else { |
| /* non-stippled */ |
| segment(ctx, &line, NAME(plot), 0.0, 1.0); |
| } |
| |
| #if defined(DO_RGBA) |
| _swrast_write_rgba_span(ctx, &(line.span)); |
| #else |
| _swrast_write_index_span(ctx, &(line.span)); |
| #endif |
| } |
| |
| |
| |
| |
| #undef DO_Z |
| #undef DO_RGBA |
| #undef DO_INDEX |
| #undef DO_ATTRIBS |
| #undef NAME |
