src/mesa/swrast/s_lines.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  5.1
   4  *
   5  * Copyright (C) 1999-2003  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 ((span->interpMask | span->arrayMask) & SPAN_TEXTURE)
  92             _swrast_write_texture_span(ctx, span);
  93          else if ((span->interpMask | span->arrayMask) & SPAN_RGBA)
  94             _swrast_write_rgba_span(ctx, span);
  95          else
  96             _swrast_write_index_span(ctx, span);
  97       }
  98    }
  99    else {
 100       GLint *x = span->array->x;
 101       GLuint i;
 102       GLint w;
 103       for (w = 0; w < width; w++) {
 104          if (w == 0) {
 105             for (i = 0; i < span->end; i++)
 106                x[i] -= start;
 107          }
 108          else {
 109             for (i = 0; i < span->end; i++)
 110                x[i]++;
 111          }
 112          if ((span->interpMask | span->arrayMask) & SPAN_TEXTURE)
 113             _swrast_write_texture_span(ctx, span);
 114          else if ((span->interpMask | span->arrayMask) & SPAN_RGBA)
 115             _swrast_write_rgba_span(ctx, span);
 116          else
 117             _swrast_write_index_span(ctx, span);
 118       }
 119    }
 120 }
 121
 122
 123
 124 /**********************************************************************/
 125 /*****                    Rasterization                           *****/
 126 /**********************************************************************/
 127
 128 /* Simple color index line (no stipple, width=1, no Z, no fog, no tex)*/
 129 #define NAME simple_ci_line
 130 #define INTERP_INDEX
 131 #define RENDER_SPAN(span) _swrast_write_index_span(ctx, &span)
 132 #include "s_linetemp.h"
 133
 134 /* Simple RGBA index line (no stipple, width=1, no Z, no fog, no tex)*/
 135 #define NAME simple_rgba_line
 136 #define INTERP_RGBA
 137 #define RENDER_SPAN(span) _swrast_write_rgba_span(ctx, &span);
 138 #include "s_linetemp.h"
 139
 140
 141 /* Z, fog, wide, stipple color index line */
 142 #define NAME general_ci_line
 143 #define INTERP_INDEX
 144 #define INTERP_Z
 145 #define INTERP_FOG
 146 #define RENDER_SPAN(span)                                       \
 147    if (ctx->Line.StippleFlag) {                                 \
 148       span.arrayMask |= SPAN_MASK;                              \
 149       compute_stipple_mask(ctx, span.end, span.array->mask);    \
 150    }                                                            \
 151    if (ctx->Line.Width > 1.0) {                                 \
 152       draw_wide_line(ctx, &span, (GLboolean)(dx > dy));         \
 153    }                                                            \
 154    else {                                                       \
 155       _swrast_write_index_span(ctx, &span);                     \
 156    }
 157 #include "s_linetemp.h"
 158
 159
 160 /* Z, fog, wide, stipple RGBA line */
 161 #define NAME general_rgba_line
 162 #define INTERP_RGBA
 163 #define INTERP_Z
 164 #define INTERP_FOG
 165 #define RENDER_SPAN(span)                                       \
 166    if (ctx->Line.StippleFlag) {                                 \
 167       span.arrayMask |= SPAN_MASK;                              \
 168       compute_stipple_mask(ctx, span.end, span.array->mask);    \
 169    }                                                            \
 170    if (ctx->Line.Width > 1.0) {                                 \
 171       draw_wide_line(ctx, &span, (GLboolean)(dx > dy));         \
 172    }                                                            \
 173    else {                                                       \
 174       _swrast_write_rgba_span(ctx, &span);                      \
 175    }
 176 #include "s_linetemp.h"
 177
 178
 179 /* Single-texture line, w/ fog, Z, specular, etc. */
 180 #define NAME textured_line
 181 #define INTERP_RGBA
 182 #define INTERP_Z
 183 #define INTERP_FOG
 184 #define INTERP_TEX
 185 #define RENDER_SPAN(span)                                       \
 186    if (ctx->Line.StippleFlag) {                                 \
 187       span.arrayMask |= SPAN_MASK;                              \
 188       compute_stipple_mask(ctx, span.end, span.array->mask);    \
 189    }                                                            \
 190    if (ctx->Line.Width > 1.0) {                                 \
 191       draw_wide_line(ctx, &span, (GLboolean)(dx > dy));         \
 192    }                                                            \
 193    else {                                                       \
 194       _swrast_write_texture_span(ctx, &span);                   \
 195    }
 196 #include "s_linetemp.h"
 197
 198
 199 /* Multi-texture or separate specular line, w/ fog, Z, specular, etc. */
 200 #define NAME multitextured_line
 201 #define INTERP_RGBA
 202 #define INTERP_SPEC
 203 #define INTERP_Z
 204 #define INTERP_FOG
 205 #define INTERP_MULTITEX
 206 #define RENDER_SPAN(span)                                       \
 207    if (ctx->Line.StippleFlag) {                                 \
 208       span.arrayMask |= SPAN_MASK;                              \
 209       compute_stipple_mask(ctx, span.end, span.array->mask);    \
 210    }                                                            \
 211    if (ctx->Line.Width > 1.0) {                                 \
 212       draw_wide_line(ctx, &span, (GLboolean)(dx > dy));         \
 213    }                                                            \
 214    else {                                                       \
 215       _swrast_write_texture_span(ctx, &span);                   \
 216    }
 217 #include "s_linetemp.h"
 218
 219
 220
 221 void
 222 _swrast_add_spec_terms_line( GLcontext *ctx,
 223                              const SWvertex *v0,
 224                              const SWvertex *v1 )
 225 {
 226    SWvertex *ncv0 = (SWvertex *)v0;
 227    SWvertex *ncv1 = (SWvertex *)v1;
 228    GLchan c[2][4];
 229    COPY_CHAN4( c[0], ncv0->color );
 230    COPY_CHAN4( c[1], ncv1->color );
 231    ACC_3V( ncv0->color, ncv0->specular );
 232    ACC_3V( ncv1->color, ncv1->specular );
 233    SWRAST_CONTEXT(ctx)->SpecLine( ctx, ncv0, ncv1 );
 234    COPY_CHAN4( ncv0->color, c[0] );
 235    COPY_CHAN4( ncv1->color, c[1] );
 236 }
 237
 238
 239 #ifdef DEBUG
 240 extern void
 241 _mesa_print_line_function(GLcontext *ctx);  /* silence compiler warning */
 242 void
 243 _mesa_print_line_function(GLcontext *ctx)
 244 {
 245    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 246
 247    _mesa_printf("Line Func == ");
 248    if (swrast->Line == simple_ci_line)
 249       _mesa_printf("simple_ci_line\n");
 250    else if (swrast->Line == simple_rgba_line)
 251       _mesa_printf("simple_rgba_line\n");
 252    else if (swrast->Line == general_ci_line)
 253       _mesa_printf("general_ci_line\n");
 254    else if (swrast->Line == general_rgba_line)
 255       _mesa_printf("general_rgba_line\n");
 256    else if (swrast->Line == textured_line)
 257       _mesa_printf("textured_line\n");
 258    else if (swrast->Line == multitextured_line)
 259       _mesa_printf("multitextured_line\n");
 260    else
 261       _mesa_printf("Driver func %p\n", (void *) swrast->Line);
 262 }
 263 #endif
 264
 265
 266
 267 #ifdef DEBUG
 268
 269 /* record the current line function name */
 270 static const char *lineFuncName = NULL;
 271
 272 #define USE(lineFunc)                   \
 273 do {                                    \
 274     lineFuncName = #lineFunc;           \
 275     /*_mesa_printf("%s\n", lineFuncName);*/   \
 276     swrast->Line = lineFunc;            \
 277 } while (0)
 278
 279 #else
 280
 281 #define USE(lineFunc)  swrast->Line = lineFunc
 282
 283 #endif
 284
 285
 286
 287 /*
 288  * Determine which line drawing function to use given the current
 289  * rendering context.
 290  *
 291  * Please update the summary flag _SWRAST_NEW_LINE if you add or remove
 292  * tests to this code.
 293  */
 294 void
 295 _swrast_choose_line( GLcontext *ctx )
 296 {
 297    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 298    const GLboolean rgbmode = ctx->Visual.rgbMode;
 299
 300    if (ctx->RenderMode == GL_RENDER) {
 301       if (ctx->Line.SmoothFlag) {
 302          /* antialiased lines */
 303          _swrast_choose_aa_line_function(ctx);
 304          ASSERT(swrast->Line);
 305       }
 306       else if (ctx->Texture._EnabledCoordUnits) {
 307          /* textured lines */
 308          if (ctx->Texture._EnabledCoordUnits > 0x1
 309              || NEED_SECONDARY_COLOR(ctx)) {
 310             /* multi-texture and/or separate specular color */
 311             USE(multitextured_line);
 312          }
 313          else {
 314             USE(textured_line);
 315          }
 316       }
 317       else if (ctx->Depth.Test || ctx->Fog.Enabled || ctx->Line.Width != 1.0
 318                || ctx->Line.StippleFlag) {
 319          /* no texture, but Z, fog, width>1, stipple, etc. */
 320          if (rgbmode)
 321             USE(general_rgba_line);
 322          else
 323             USE(general_ci_line);
 324       }
 325       else {
 326          /* simplest lines */
 327          if (rgbmode)
 328             USE(simple_rgba_line);
 329          else
 330             USE(simple_ci_line);
 331       }
 332    }
 333    else if (ctx->RenderMode == GL_FEEDBACK) {
 334       USE(_swrast_feedback_line);
 335    }
 336    else {
 337       ASSERT(ctx->RenderMode == GL_SELECT);
 338       USE(_swrast_select_line);
 339    }
 340
 341    /*_mesa_print_line_function(ctx);*/
 342 }