/* $Id: s_linetemp.h,v 1.6 2001/03/08 17:33:33 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. */ /* * Line Rasterizer Template * * This file is #include'd to generate custom line rasterizers. * * The following macros may be defined to indicate what auxillary information * must be interplated along the line: * INTERP_Z - if defined, interpolate Z values * INTERP_FOG - if defined, interpolate FOG values * INTERP_RGB - if defined, interpolate RGB values * INTERP_SPEC - if defined, interpolate specular RGB values * INTERP_ALPHA - if defined, interpolate Alpha values * INTERP_INDEX - if defined, interpolate color index values * INTERP_TEX - if defined, interpolate unit 0 texcoords * INTERP_MULTITEX - if defined, interpolate multi-texcoords * * When one can directly address pixels in the color buffer the following * macros can be defined and used to directly compute pixel addresses during * rasterization (see pixelPtr): * PIXEL_TYPE - the datatype of a pixel (GLubyte, GLushort, GLuint) * BYTES_PER_ROW - number of bytes per row in the color buffer * PIXEL_ADDRESS(X,Y) - returns the address of pixel at (X,Y) where * Y==0 at bottom of screen and increases upward. * * Similarly, for direct depth buffer access, this type is used for depth * buffer addressing: * DEPTH_TYPE - either GLushort or GLuint * * Optionally, one may provide one-time setup code * SETUP_CODE - code which is to be executed once per line * * To enable line stippling define STIPPLE = 1 * To enable wide lines define WIDE = 1 * * To actually "plot" each pixel either the PLOT macro or * (XMAJOR_PLOT and YMAJOR_PLOT macros) must be defined... * PLOT(X,Y) - code to plot a pixel. Example: * if (Z < *zPtr) { * *zPtr = Z; * color = pack_rgb( FixedToInt(r0), FixedToInt(g0), * FixedToInt(b0) ); * put_pixel( X, Y, color ); * } * * This code was designed for the origin to be in the lower-left corner. * */ /*void line( GLcontext *ctx, const SWvertex *vert0, const SWvertex *vert1 )*/ { GLint x0 = (GLint) vert0->win[0]; GLint x1 = (GLint) vert1->win[0]; GLint y0 = (GLint) vert0->win[1]; GLint y1 = (GLint) vert1->win[1]; GLint dx, dy; #ifdef INTERP_XY GLint xstep, ystep; #endif #ifdef INTERP_Z GLint z0, z1, dz; const GLint depthBits = ctx->Visual.depthBits; const GLint fixedToDepthShift = depthBits <= 16 ? FIXED_SHIFT : 0; # define FixedToDepth(F) ((F) >> fixedToDepthShift) # ifdef DEPTH_TYPE GLint zPtrXstep, zPtrYstep; DEPTH_TYPE *zPtr; # endif #endif #ifdef INTERP_FOG GLfixed fog0 = FloatToFixed(vert0->fog); GLfixed dfog = FloatToFixed(vert1->fog) - fog0; #endif #ifdef INTERP_RGB GLfixed r0 = IntToFixed(vert0->color[0]); GLfixed dr = IntToFixed(vert1->color[0]) - r0; GLfixed g0 = IntToFixed(vert0->color[1]); GLfixed dg = IntToFixed(vert1->color[1]) - g0; GLfixed b0 = IntToFixed(vert0->color[2]); GLfixed db = IntToFixed(vert1->color[2]) - b0; #endif #ifdef INTERP_SPEC GLfixed sr0 = IntToFixed(vert0->specular[0]); GLfixed dsr = IntToFixed(vert1->specular[0]) - sr0; GLfixed sg0 = IntToFixed(vert0->specular[1]); GLfixed dsg = IntToFixed(vert1->specular[1]) - sg0; GLfixed sb0 = IntToFixed(vert0->specular[2]); GLfixed dsb = IntToFixed(vert1->specular[2]) - sb0; #endif #ifdef INTERP_ALPHA GLfixed a0 = IntToFixed(vert0->color[3]); GLfixed da = IntToFixed(vert1->color[3]) - a0; #endif #ifdef INTERP_INDEX GLint i0 = vert0->index << 8; GLint di = (GLint) (vert1->index << 8) - i0; #endif #ifdef INTERP_TEX const GLfloat invw0 = vert0->win[3]; const GLfloat invw1 = vert1->win[3]; GLfloat tex[4]; GLfloat dtex[4]; GLfloat fragTexcoord[4]; #endif #ifdef INTERP_MULTITEX const GLfloat invw0 = vert0->win[3]; const GLfloat invw1 = vert1->win[3]; GLfloat tex[MAX_TEXTURE_UNITS][4]; GLfloat dtex[MAX_TEXTURE_UNITS][4]; GLfloat fragTexcoord[MAX_TEXTURE_UNITS][4]; #endif #ifdef PIXEL_ADDRESS PIXEL_TYPE *pixelPtr; GLint pixelXstep, pixelYstep; #endif #ifdef STIPPLE SWcontext *swrast = SWRAST_CONTEXT(ctx); #endif #ifdef WIDE /* for wide lines, draw all X in [x+min, x+max] or Y in [y+min, y+max] */ GLint width, min, max; width = (GLint) CLAMP( ctx->Line.Width, MIN_LINE_WIDTH, MAX_LINE_WIDTH ); min = (width-1) / -2; max = min + width - 1; #endif #ifdef INTERP_TEX { tex[0] = invw0 * vert0->texcoord[0][0]; dtex[0] = invw1 * vert1->texcoord[0][0] - tex[0]; tex[1] = invw0 * vert0->texcoord[0][1]; dtex[1] = invw1 * vert1->texcoord[0][1] - tex[1]; tex[2] = invw0 * vert0->texcoord[0][2]; dtex[2] = invw1 * vert1->texcoord[0][2] - tex[2]; tex[3] = invw0 * vert0->texcoord[0][3]; dtex[3] = invw1 * vert1->texcoord[0][3] - tex[3]; } #endif #ifdef INTERP_MULTITEX { GLuint u; for (u = 0; u < ctx->Const.MaxTextureUnits; u++) { if (ctx->Texture.Unit[u]._ReallyEnabled) { tex[u][0] = invw0 * vert0->texcoord[u][0]; dtex[u][0] = invw1 * vert1->texcoord[u][0] - tex[u][0]; tex[u][1] = invw0 * vert0->texcoord[u][1]; dtex[u][1] = invw1 * vert1->texcoord[u][1] - tex[u][1]; tex[u][2] = invw0 * vert0->texcoord[u][2]; dtex[u][2] = invw1 * vert1->texcoord[u][2] - tex[u][2]; tex[u][3] = invw0 * vert0->texcoord[u][3]; dtex[u][3] = invw1 * vert1->texcoord[u][3] - tex[u][3]; } } } #endif /* * Despite being clipped to the view volume, the line's window coordinates * may just lie outside the window bounds. That is, if the legal window * coordinates are [0,W-1][0,H-1], it's possible for x==W and/or y==H. * This quick and dirty code nudges the endpoints inside the window if * necessary. */ #ifdef CLIP_HACK { GLint w = ctx->DrawBuffer->Width; GLint h = ctx->DrawBuffer->Height; if ((x0==w) | (x1==w)) { if ((x0==w) & (x1==w)) return; x0 -= x0==w; x1 -= x1==w; } if ((y0==h) | (y1==h)) { if ((y0==h) & (y1==h)) return; y0 -= y0==h; y1 -= y1==h; } } #endif dx = x1 - x0; dy = y1 - y0; if (dx==0 && dy==0) { return; } /* * Setup */ #ifdef SETUP_CODE SETUP_CODE #endif #ifdef INTERP_Z # ifdef DEPTH_TYPE zPtr = (DEPTH_TYPE *) _mesa_zbuffer_address(ctx, x0, y0); # endif if (depthBits <= 16) { z0 = FloatToFixed(vert0->win[2]); z1 = FloatToFixed(vert1->win[2]); } else { z0 = (int) vert0->win[2]; z1 = (int) vert1->win[2]; } #endif #ifdef PIXEL_ADDRESS pixelPtr = (PIXEL_TYPE *) PIXEL_ADDRESS(x0,y0); #endif if (dx<0) { dx = -dx; /* make positive */ #ifdef INTERP_XY xstep = -1; #endif #if defined(INTERP_Z) && defined(DEPTH_TYPE) zPtrXstep = -((GLint)sizeof(DEPTH_TYPE)); #endif #ifdef PIXEL_ADDRESS pixelXstep = -((GLint)sizeof(PIXEL_TYPE)); #endif } else { #ifdef INTERP_XY xstep = 1; #endif #if defined(INTERP_Z) && defined(DEPTH_TYPE) zPtrXstep = ((GLint)sizeof(DEPTH_TYPE)); #endif #ifdef PIXEL_ADDRESS pixelXstep = ((GLint)sizeof(PIXEL_TYPE)); #endif } if (dy<0) { dy = -dy; /* make positive */ #ifdef INTERP_XY ystep = -1; #endif #if defined(INTERP_Z) && defined(DEPTH_TYPE) zPtrYstep = -ctx->DrawBuffer->Width * ((GLint)sizeof(DEPTH_TYPE)); #endif #ifdef PIXEL_ADDRESS pixelYstep = BYTES_PER_ROW; #endif } else { #ifdef INTERP_XY ystep = 1; #endif #if defined(INTERP_Z) && defined(DEPTH_TYPE) zPtrYstep = ctx->DrawBuffer->Width * ((GLint)sizeof(DEPTH_TYPE)); #endif #ifdef PIXEL_ADDRESS pixelYstep = -(BYTES_PER_ROW); #endif } /* * Draw */ if (dx>dy) { /*** X-major line ***/ GLint i; GLint errorInc = dy+dy; GLint error = errorInc-dx; GLint errorDec = error-dx; #ifdef INTERP_Z dz = (z1-z0) / dx; #endif #ifdef INTERP_FOG dfog /= dx; #endif #ifdef INTERP_RGB dr /= dx; /* convert from whole line delta to per-pixel delta */ dg /= dx; db /= dx; #endif #ifdef INTERP_SPEC dsr /= dx; /* convert from whole line delta to per-pixel delta */ dsg /= dx; dsb /= dx; #endif #ifdef INTERP_ALPHA da /= dx; #endif #ifdef INTERP_INDEX di /= dx; #endif #ifdef INTERP_TEX { const GLfloat invDx = 1.0F / (GLfloat) dx; dtex[0] *= invDx; dtex[1] *= invDx; dtex[2] *= invDx; dtex[3] *= invDx; } #endif #ifdef INTERP_MULTITEX { const GLfloat invDx = 1.0F / (GLfloat) dx; GLuint u; for (u = 0; u < ctx->Const.MaxTextureUnits; u++) { if (ctx->Texture.Unit[u]._ReallyEnabled) { dtex[u][0] *= invDx; dtex[u][1] *= invDx; dtex[u][2] *= invDx; dtex[u][3] *= invDx; } } } #endif for (i=0;iStippleCounter/ctx->Line.StippleFactor) & 0xf); if (ctx->Line.StipplePattern & m) { #endif #ifdef INTERP_Z GLdepth Z = FixedToDepth(z0); #endif #ifdef INTERP_INDEX GLint I = i0 >> 8; #endif #ifdef INTERP_TEX { const GLfloat invQ = tex[3] ? (1.0F / tex[3]) : 1.0F; fragTexcoord[0] = tex[0] * invQ; fragTexcoord[1] = tex[1] * invQ; fragTexcoord[2] = tex[2] * invQ; fragTexcoord[3] = tex[3]; } #endif #ifdef INTERP_MULTITEX { GLuint u; for (u = 0; u < ctx->Const.MaxTextureUnits; u++) { if (ctx->Texture.Unit[u]._ReallyEnabled) { const GLfloat invQ = 1.0F / tex[u][3]; fragTexcoord[u][0] = tex[u][0] * invQ; fragTexcoord[u][1] = tex[u][1] * invQ; fragTexcoord[u][2] = tex[u][2] * invQ; fragTexcoord[u][3] = tex[u][3]; } } } #endif #ifdef WIDE { GLint yy; GLint ymin = y0 + min; GLint ymax = y0 + max; for (yy=ymin;yy<=ymax;yy++) { PLOT( x0, yy ); } } #else # ifdef XMAJOR_PLOT XMAJOR_PLOT( x0, y0 ); # else PLOT( x0, y0 ); # endif #endif /*WIDE*/ #ifdef STIPPLE } swrast->StippleCounter++; #endif #ifdef INTERP_XY x0 += xstep; #endif #ifdef INTERP_Z # ifdef DEPTH_TYPE zPtr = (DEPTH_TYPE *) ((GLubyte*) zPtr + zPtrXstep); # endif z0 += dz; #endif #ifdef INTERP_FOG fog0 += dfog; #endif #ifdef INTERP_RGB r0 += dr; g0 += dg; b0 += db; #endif #ifdef INTERP_SPEC sr0 += dsr; sg0 += dsg; sb0 += dsb; #endif #ifdef INTERP_ALPHA a0 += da; #endif #ifdef INTERP_INDEX i0 += di; #endif #ifdef INTERP_TEX tex[0] += dtex[0]; tex[1] += dtex[1]; tex[2] += dtex[2]; tex[3] += dtex[3]; #endif #ifdef INTERP_MULTITEX { GLuint u; for (u = 0; u < ctx->Const.MaxTextureUnits; u++) { if (ctx->Texture.Unit[u]._ReallyEnabled) { tex[u][0] += dtex[u][0]; tex[u][1] += dtex[u][1]; tex[u][2] += dtex[u][2]; tex[u][3] += dtex[u][3]; } } } #endif #ifdef PIXEL_ADDRESS pixelPtr = (PIXEL_TYPE*) ((GLubyte*) pixelPtr + pixelXstep); #endif if (error<0) { error += errorInc; } else { error += errorDec; #ifdef INTERP_XY y0 += ystep; #endif #if defined(INTERP_Z) && defined(DEPTH_TYPE) zPtr = (DEPTH_TYPE *) ((GLubyte*) zPtr + zPtrYstep); #endif #ifdef PIXEL_ADDRESS pixelPtr = (PIXEL_TYPE*) ((GLubyte*) pixelPtr + pixelYstep); #endif } } } else { /*** Y-major line ***/ GLint i; GLint errorInc = dx+dx; GLint error = errorInc-dy; GLint errorDec = error-dy; #ifdef INTERP_Z dz = (z1-z0) / dy; #endif #ifdef INTERP_FOG dfog /= dy; #endif #ifdef INTERP_RGB dr /= dy; /* convert from whole line delta to per-pixel delta */ dg /= dy; db /= dy; #endif #ifdef INTERP_SPEC dsr /= dy; /* convert from whole line delta to per-pixel delta */ dsg /= dy; dsb /= dy; #endif #ifdef INTERP_ALPHA da /= dy; #endif #ifdef INTERP_INDEX di /= dy; #endif #ifdef INTERP_TEX { const GLfloat invDy = 1.0F / (GLfloat) dy; dtex[0] *= invDy; dtex[1] *= invDy; dtex[2] *= invDy; dtex[3] *= invDy; } #endif #ifdef INTERP_MULTITEX { const GLfloat invDy = 1.0F / (GLfloat) dy; GLuint u; for (u = 0; u < ctx->Const.MaxTextureUnits; u++) { if (ctx->Texture.Unit[u]._ReallyEnabled) { dtex[u][0] *= invDy; dtex[u][1] *= invDy; dtex[u][2] *= invDy; dtex[u][3] *= invDy; } } } #endif for (i=0;iStippleCounter/ctx->Line.StippleFactor) & 0xf); if (ctx->Line.StipplePattern & m) { #endif #ifdef INTERP_Z GLdepth Z = FixedToDepth(z0); #endif #ifdef INTERP_INDEX GLint I = i0 >> 8; #endif #ifdef INTERP_TEX { const GLfloat invQ = tex[3] ? (1.0F / tex[3]) : 1.0F; fragTexcoord[0] = tex[0] * invQ; fragTexcoord[1] = tex[1] * invQ; fragTexcoord[2] = tex[2] * invQ; fragTexcoord[3] = tex[3]; } #endif #ifdef INTERP_MULTITEX { GLuint u; for (u = 0; u < ctx->Const.MaxTextureUnits; u++) { if (ctx->Texture.Unit[u]._ReallyEnabled) { const GLfloat invQ = 1.0F / tex[u][3]; fragTexcoord[u][0] = tex[u][0] * invQ; fragTexcoord[u][1] = tex[u][1] * invQ; fragTexcoord[u][2] = tex[u][2] * invQ; fragTexcoord[u][3] = tex[u][3]; } } } #endif #ifdef WIDE { GLint xx; GLint xmin = x0 + min; GLint xmax = x0 + max; for (xx=xmin;xx<=xmax;xx++) { PLOT( xx, y0 ); } } #else # ifdef YMAJOR_PLOT YMAJOR_PLOT( x0, y0 ); # else PLOT( x0, y0 ); # endif #endif /*WIDE*/ #ifdef STIPPLE } swrast->StippleCounter++; #endif #ifdef INTERP_XY y0 += ystep; #endif #ifdef INTERP_Z # ifdef DEPTH_TYPE zPtr = (DEPTH_TYPE *) ((GLubyte*) zPtr + zPtrYstep); # endif z0 += dz; #endif #ifdef INTERP_FOG fog0 += dfog; #endif #ifdef INTERP_RGB r0 += dr; g0 += dg; b0 += db; #endif #ifdef INTERP_SPEC sr0 += dsr; sg0 += dsg; sb0 += dsb; #endif #ifdef INTERP_ALPHA a0 += da; #endif #ifdef INTERP_INDEX i0 += di; #endif #ifdef INTERP_TEX tex[0] += dtex[0]; tex[1] += dtex[1]; tex[2] += dtex[2]; tex[3] += dtex[3]; #endif #ifdef INTERP_MULTITEX { GLuint u; for (u = 0; u < ctx->Const.MaxTextureUnits; u++) { if (ctx->Texture.Unit[u]._ReallyEnabled) { tex[u][0] += dtex[u][0]; tex[u][1] += dtex[u][1]; tex[u][2] += dtex[u][2]; tex[u][3] += dtex[u][3]; } } } #endif #ifdef PIXEL_ADDRESS pixelPtr = (PIXEL_TYPE*) ((GLubyte*) pixelPtr + pixelYstep); #endif if (error<0) { error += errorInc; } else { error += errorDec; #ifdef INTERP_XY x0 += xstep; #endif #if defined(INTERP_Z) && defined(DEPTH_TYPE) zPtr = (DEPTH_TYPE *) ((GLubyte*) zPtr + zPtrXstep); #endif #ifdef PIXEL_ADDRESS pixelPtr = (PIXEL_TYPE*) ((GLubyte*) pixelPtr + pixelXstep); #endif } } } } #undef INTERP_XY #undef INTERP_Z #undef INTERP_FOG #undef INTERP_RGB #undef INTERP_SPEC #undef INTERP_ALPHA #undef INTERP_TEX #undef INTERP_MULTITEX #undef INTERP_INDEX #undef PIXEL_ADDRESS #undef PIXEL_TYPE #undef DEPTH_TYPE #undef BYTES_PER_ROW #undef SETUP_CODE #undef PLOT #undef XMAJOR_PLOT #undef YMAJOR_PLOT #undef CLIP_HACK #undef STIPPLE #undef WIDE #undef FixedToDepth