src/mesa/swrast/s_lines.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  6.3
   4  *
   5  * Copyright (C) 1999-2004  Brian Paul   All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25
  26 #include "glheader.h"
  27 #include "context.h"
  28 #include "colormac.h"
  29 #include "macros.h"
  30 #include "nvfragprog.h"
  31 #include "s_aaline.h"
  32 #include "s_context.h"
  33 #include "s_depth.h"
  34 #include "s_feedback.h"
  35 #include "s_lines.h"
  36 #include "s_span.h"
  37
  38
  39 /*
  40  * Init the mask[] array to implement a line stipple.
  41  */
  42 static void
  43 compute_stipple_mask( GLcontext *ctx, GLuint len, GLubyte mask[] )
  44 {
  45    SWcontext *swrast = SWRAST_CONTEXT(ctx);
  46    GLuint i;
  47
  48    for (i = 0; i < len; i++) {
  49       GLuint bit = (swrast->StippleCounter / ctx->Line.StippleFactor) & 0xf;
  50       if ((1 << bit) & ctx->Line.StipplePattern) {
  51          mask[i] = GL_TRUE;
  52       }
  53       else {
  54          mask[i] = GL_FALSE;
  55       }
  56       swrast->StippleCounter++;
  57    }
  58 }
  59
  60
  61 /*
  62  * To draw a wide line we can simply redraw the span N times, side by side.
  63  */
  64 static void
  65 draw_wide_line( GLcontext *ctx, struct sw_span *span, GLboolean xMajor )
  66 {
  67    GLint width, start;
  68
  69    ASSERT(span->end < MAX_WIDTH);
  70
  71    width = (GLint) CLAMP( ctx->Line.Width, MIN_LINE_WIDTH, MAX_LINE_WIDTH );
  72
  73    if (width & 1)
  74       start = width / 2;
  75    else
  76       start = width / 2 - 1;
  77
  78    if (xMajor) {
  79       GLint *y = span->array->y;
  80       GLuint i;
  81       GLint w;
  82       for (w = 0; w < width; w++) {
  83          if (w == 0) {
  84             for (i = 0; i < span->end; i++)
  85                y[i] -= start;
  86          }
  87          else {
  88             for (i = 0; i < span->end; i++)
  89                y[i]++;
  90          }
  91          if (ctx->Visual.rgbMode)
  92             _swrast_write_rgba_span(ctx, span);
  93          else
  94             _swrast_write_index_span(ctx, span);
  95       }
  96    }
  97    else {
  98       GLint *x = span->array->x;
  99       GLuint i;
 100       GLint w;
 101       for (w = 0; w < width; w++) {
 102          if (w == 0) {
 103             for (i = 0; i < span->end; i++)
 104                x[i] -= start;
 105          }
 106          else {
 107             for (i = 0; i < span->end; i++)
 108                x[i]++;
 109          }
 110          if (ctx->Visual.rgbMode)
 111             _swrast_write_rgba_span(ctx, span);
 112          else
 113             _swrast_write_index_span(ctx, span);
 114       }
 115    }
 116 }
 117
 118
 119
 120 /**********************************************************************/
 121 /*****                    Rasterization                           *****/
 122 /**********************************************************************/
 123
 124 /* Simple color index line (no stipple, width=1, no Z, no fog, no tex)*/
 125 #define NAME simple_ci_line
 126 #define INTERP_INDEX
 127 #define RENDER_SPAN(span) _swrast_write_index_span(ctx, &span)
 128 #include "s_linetemp.h"
 129
 130 /* Simple RGBA index line (no stipple, width=1, no Z, no fog, no tex)*/
 131 #define NAME simple_rgba_line
 132 #define INTERP_RGBA
 133 #define RENDER_SPAN(span) _swrast_write_rgba_span(ctx, &span);
 134 #include "s_linetemp.h"
 135
 136
 137 /* Z, fog, wide, stipple color index line */
 138 #define NAME general_ci_line
 139 #define INTERP_INDEX
 140 #define INTERP_Z
 141 #define INTERP_FOG
 142 #define RENDER_SPAN(span)                                       \
 143    if (ctx->Line.StippleFlag) {                                 \
 144       span.arrayMask |= SPAN_MASK;                              \
 145       compute_stipple_mask(ctx, span.end, span.array->mask);    \
 146    }                                                            \
 147    if (ctx->Line.Width > 1.0) {                                 \
 148       draw_wide_line(ctx, &span, (GLboolean)(dx > dy));         \
 149    }                                                            \
 150    else {                                                       \
 151       _swrast_write_index_span(ctx, &span);                     \
 152    }
 153 #include "s_linetemp.h"
 154
 155
 156 /* Z, fog, wide, stipple RGBA line */
 157 #define NAME general_rgba_line
 158 #define INTERP_RGBA
 159 #define INTERP_Z
 160 #define INTERP_FOG
 161 #define RENDER_SPAN(span)                                       \
 162    if (ctx->Line.StippleFlag) {                                 \
 163       span.arrayMask |= SPAN_MASK;                              \
 164       compute_stipple_mask(ctx, span.end, span.array->mask);    \
 165    }                                                            \
 166    if (ctx->Line.Width > 1.0) {                                 \
 167       draw_wide_line(ctx, &span, (GLboolean)(dx > dy));         \
 168    }                                                            \
 169    else {                                                       \
 170       _swrast_write_rgba_span(ctx, &span);                      \
 171    }
 172 #include "s_linetemp.h"
 173
 174
 175 /* Single-texture line, w/ fog, Z, specular, etc. */
 176 #define NAME textured_line
 177 #define INTERP_RGBA
 178 #define INTERP_Z
 179 #define INTERP_FOG
 180 #define INTERP_TEX
 181 #define RENDER_SPAN(span)                                       \
 182    if (ctx->Line.StippleFlag) {                                 \
 183       span.arrayMask |= SPAN_MASK;                              \
 184       compute_stipple_mask(ctx, span.end, span.array->mask);    \
 185    }                                                            \
 186    if (ctx->Line.Width > 1.0) {                                 \
 187       draw_wide_line(ctx, &span, (GLboolean)(dx > dy));         \
 188    }                                                            \
 189    else {                                                       \
 190       _swrast_write_rgba_span(ctx, &span);                      \
 191    }
 192 #include "s_linetemp.h"
 193
 194
 195 /* Multi-texture or separate specular line, w/ fog, Z, specular, etc. */
 196 #define NAME multitextured_line
 197 #define INTERP_RGBA
 198 #define INTERP_SPEC
 199 #define INTERP_Z
 200 #define INTERP_FOG
 201 #define INTERP_MULTITEX
 202 #define RENDER_SPAN(span)                                       \
 203    if (ctx->Line.StippleFlag) {                                 \
 204       span.arrayMask |= SPAN_MASK;                              \
 205       compute_stipple_mask(ctx, span.end, span.array->mask);    \
 206    }                                                            \
 207    if (ctx->Line.Width > 1.0) {                                 \
 208       draw_wide_line(ctx, &span, (GLboolean)(dx > dy));         \
 209    }                                                            \
 210    else {                                                       \
 211       _swrast_write_rgba_span(ctx, &span);                      \
 212    }
 213 #include "s_linetemp.h"
 214
 215
 216
 217 void
 218 _swrast_add_spec_terms_line( GLcontext *ctx,
 219                              const SWvertex *v0,
 220                              const SWvertex *v1 )
 221 {
 222    SWvertex *ncv0 = (SWvertex *)v0;
 223    SWvertex *ncv1 = (SWvertex *)v1;
 224    GLchan c[2][4];
 225    COPY_CHAN4( c[0], ncv0->color );
 226    COPY_CHAN4( c[1], ncv1->color );
 227    ACC_3V( ncv0->color, ncv0->specular );
 228    ACC_3V( ncv1->color, ncv1->specular );
 229    SWRAST_CONTEXT(ctx)->SpecLine( ctx, ncv0, ncv1 );
 230    COPY_CHAN4( ncv0->color, c[0] );
 231    COPY_CHAN4( ncv1->color, c[1] );
 232 }
 233
 234
 235 #ifdef DEBUG
 236 extern void
 237 _mesa_print_line_function(GLcontext *ctx);  /* silence compiler warning */
 238 void
 239 _mesa_print_line_function(GLcontext *ctx)
 240 {
 241    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 242
 243    _mesa_printf("Line Func == ");
 244    if (swrast->Line == simple_ci_line)
 245       _mesa_printf("simple_ci_line\n");
 246    else if (swrast->Line == simple_rgba_line)
 247       _mesa_printf("simple_rgba_line\n");
 248    else if (swrast->Line == general_ci_line)
 249       _mesa_printf("general_ci_line\n");
 250    else if (swrast->Line == general_rgba_line)
 251       _mesa_printf("general_rgba_line\n");
 252    else if (swrast->Line == textured_line)
 253       _mesa_printf("textured_line\n");
 254    else if (swrast->Line == multitextured_line)
 255       _mesa_printf("multitextured_line\n");
 256    else
 257       _mesa_printf("Driver func %p\n", (void *(*)()) swrast->Line);
 258 }
 259 #endif
 260
 261
 262
 263 #ifdef DEBUG
 264
 265 /* record the current line function name */
 266 static const char *lineFuncName = NULL;
 267
 268 #define USE(lineFunc)                   \
 269 do {                                    \
 270     lineFuncName = #lineFunc;           \
 271     /*_mesa_printf("%s\n", lineFuncName);*/   \
 272     swrast->Line = lineFunc;            \
 273 } while (0)
 274
 275 #else
 276
 277 #define USE(lineFunc)  swrast->Line = lineFunc
 278
 279 #endif
 280
 281
 282
 283 /*
 284  * Determine which line drawing function to use given the current
 285  * rendering context.
 286  *
 287  * Please update the summary flag _SWRAST_NEW_LINE if you add or remove
 288  * tests to this code.
 289  */
 290 void
 291 _swrast_choose_line( GLcontext *ctx )
 292 {
 293    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 294    const GLboolean rgbmode = ctx->Visual.rgbMode;
 295
 296    if (ctx->RenderMode == GL_RENDER) {
 297       if (ctx->Line.SmoothFlag) {
 298          /* antialiased lines */
 299          _swrast_choose_aa_line_function(ctx);
 300          ASSERT(swrast->Line);
 301       }
 302       else if (ctx->Texture._EnabledCoordUnits) {
 303          /* textured lines */
 304          if (ctx->Texture._EnabledCoordUnits > 0x1
 305              || NEED_SECONDARY_COLOR(ctx)) {
 306             /* multi-texture and/or separate specular color */
 307             USE(multitextured_line);
 308          }
 309          else {
 310             USE(textured_line);
 311          }
 312       }
 313       else if (ctx->Depth.Test || ctx->Fog.Enabled || ctx->Line.Width != 1.0
 314                || ctx->Line.StippleFlag) {
 315          /* no texture, but Z, fog, width>1, stipple, etc. */
 316          if (rgbmode)
 317             USE(general_rgba_line);
 318          else
 319             USE(general_ci_line);
 320       }
 321       else {
 322          /* simplest lines */
 323          if (rgbmode)
 324             USE(simple_rgba_line);
 325          else
 326             USE(simple_ci_line);
 327       }
 328    }
 329    else if (ctx->RenderMode == GL_FEEDBACK) {
 330       USE(_swrast_feedback_line);
 331    }
 332    else {
 333       ASSERT(ctx->RenderMode == GL_SELECT);
 334       USE(_swrast_select_line);
 335    }
 336
 337    /*_mesa_print_line_function(ctx);*/
 338 }