/* -*- mode: C; tab-width:8; -*- fxrender.c - 3Dfx VooDoo RenderVB driver function support */ /* * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the Free * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * * See the file fxapi.c for more informations about authors * */ #if defined(FX) #include "fxdrv.h" /* * Render a line segment from VB[v1] to VB[v2] when either one or both * endpoints must be clipped. */ static void fxRenderClippedLine( GLcontext *ctx, GLuint v1, GLuint v2 ) { GLfloat ndc_x,ndc_y,ndc_z; struct vertex_buffer *VB=ctx->VB; fxMesaContext fxMesa=(fxMesaContext)ctx->DriverCtx; GrVertex *gWin=fxMesa->gWin; /* * Clipping may introduce new vertices. New vertices will be stored * in the vertex buffer arrays starting with location VB->Free. After * we've rendered the line, these extra vertices can be overwritten. */ VB->Free = VB_MAX; /* Clip against view volume */ if (gl_viewclip_line( ctx, &v1, &v2 )==0) return; /* Transform from clip coords to ndc: ndc = clip / W */ if (VB->Clip[v1][3] != 0.0F) { GLfloat wInv = 1.0F / VB->Clip[v1][3]; ndc_x = VB->Clip[v1][0] * wInv; ndc_y = VB->Clip[v1][1] * wInv; ndc_z = VB->Clip[v1][2] * wInv; } else { /* Can't divide by zero, so... */ ndc_x = ndc_y = ndc_z = 0.0F; } /* Map ndc coord to window coords. */ VB->Win[v1][0] = ndc_x * ctx->Viewport.Sx + ctx->Viewport.Tx; VB->Win[v1][1] = ndc_y * ctx->Viewport.Sy + ctx->Viewport.Ty; VB->Win[v1][2] = ndc_z * ctx->Viewport.Sz + ctx->Viewport.Tz; /* Transform from clip coords to ndc: ndc = clip / W */ if (VB->Clip[v2][3] != 0.0F) { GLfloat wInv = 1.0F / VB->Clip[v2][3]; ndc_x = VB->Clip[v2][0] * wInv; ndc_y = VB->Clip[v2][1] * wInv; ndc_z = VB->Clip[v2][2] * wInv; } else { /* Can't divide by zero, so... */ ndc_x = ndc_y = ndc_z = 0.0F; } /* Map ndc coord to window coords. */ VB->Win[v2][0] = ndc_x * ctx->Viewport.Sx + ctx->Viewport.Tx; VB->Win[v2][1] = ndc_y * ctx->Viewport.Sy + ctx->Viewport.Ty; VB->Win[v2][2] = ndc_z * ctx->Viewport.Sz + ctx->Viewport.Tz; (*ctx->Driver.RasterSetup)(ctx,v1,v1+1); (*ctx->Driver.RasterSetup)(ctx,v2,v2+1); grDrawLine(&gWin[v1],&gWin[v2]); } /* * Render a polygon in which at least one vertex has to be clipped. * Input: n - number of vertices * vlist - list of vertices in the polygon. * CCW order = front facing. */ static void fxRenderClippedPolygon( GLcontext *ctx, GLuint n, GLuint vlist[] ) { struct vertex_buffer *VB = ctx->VB; GLfloat (*win)[3] = VB->Win; fxMesaContext fxMesa=(fxMesaContext)ctx->DriverCtx; GrVertex *gWin=fxMesa->gWin; /* * Clipping may introduce new vertices. New vertices will be stored * in the vertex buffer arrays starting with location VB->Free. After * we've rendered the polygon, these extra vertices can be overwritten. */ VB->Free = VB_MAX; /* Clip against view volume in clip coord space */ n = gl_viewclip_polygon( ctx, n, vlist ); if (n<3) return; /* Transform new vertices from clip to ndc to window coords. */ /* ndc = clip / W window = viewport_mapping(ndc) */ /* Note that window Z values are scaled to the range of integer */ /* depth buffer values. */ { GLfloat sx = ctx->Viewport.Sx; GLfloat tx = ctx->Viewport.Tx; GLfloat sy = ctx->Viewport.Sy; GLfloat ty = ctx->Viewport.Ty; GLfloat sz = ctx->Viewport.Sz; GLfloat tz = ctx->Viewport.Tz; GLuint i; /* Only need to compute window coords for new vertices */ for (i=VB_MAX; iFree; i++) { if (VB->Clip[i][3] != 0.0F) { GLfloat wInv = 1.0F / VB->Clip[i][3]; win[i][0] = VB->Clip[i][0] * wInv * sx + tx; win[i][1] = VB->Clip[i][1] * wInv * sy + ty; win[i][2] = VB->Clip[i][2] * wInv * sz + tz; } else { /* Can't divide by zero, so... */ win[i][0] = win[i][1] = win[i][2] = 0.0F; } } if(VB->Free > VB_MAX) (*ctx->Driver.RasterSetup)(ctx,VB_MAX,VB->Free); } { GLint i; GLuint j0=vlist[0]; for (i=2;iColor[pv][0], \ VB->Color[pv][1], \ VB->Color[pv][2], \ VB->Color[pv][3])); #include "fxrender.h" #undef FXRENDERVB_NAME #undef RVB_COLOR #define FXRENDERVB_NAME fxDDRenderVBSmooth #define RVB_COLOR(pv) #include "fxrender.h" #undef FXRENDERVB_NAME #undef RVB_COLOR tfxRenderVBFunc fxDDChooseRenderVBFunction(GLcontext *ctx) { fxMesaContext fxMesa=(fxMesaContext)ctx->DriverCtx; if((ctx->RasterMask & FRONT_AND_BACK_BIT) || (ctx->Polygon.OffsetAny) || /* Not yet supported */ (ctx->Light.Model.TwoSide) || (ctx->Transform.AnyClip) || (ctx->Point.SmoothFlag) || (ctx->Line.SmoothFlag) || (ctx->Polygon.Unfilled) || (ctx->Polygon.SmoothFlag) || (ctx->Polygon.StippleFlag) || (ctx->RenderMode!=GL_RENDER)) { grCullMode(GR_CULL_DISABLE); return NULL; } fxMesa->currentFrontFace=ctx->Polygon.FrontFace; if(ctx->Polygon.CullFlag) { switch(ctx->Polygon.CullFaceMode) { case GL_BACK: if(ctx->Polygon.FrontFace==GL_CCW) grCullMode(GR_CULL_NEGATIVE); else grCullMode(GR_CULL_POSITIVE); break; case GL_FRONT: if(ctx->Polygon.FrontFace==GL_CCW) grCullMode(GR_CULL_POSITIVE); else grCullMode(GR_CULL_NEGATIVE); break; case GL_FRONT_AND_BACK: grCullMode(GR_CULL_DISABLE); return NULL; default: ; /*nothing*/ } } else grCullMode(GR_CULL_DISABLE); if(ctx->Light.ShadeModel==GL_SMOOTH) return fxDDRenderVBSmooth; return fxDDRenderVBFlat; } #else /* * Need this to provide at least one external definition. */ int gl_fx_dummy_function_render(void) { return 0; } #endif /* FX */