t_dd_dmatmp.h

这是一个开放源代码的与WINNT/WIN2K/WIN2003兼容的操作系统

/*
 * Mesa 3-D graphics library
 * Version:  6.1
 *
 * Copyright (C) 1999-2004  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.
 *
 * Authors:
 *    Keith Whitwell <[e-mail]>
 */


/* Template for render stages which build and emit vertices directly
 * to fixed-size dma buffers.  Useful for rendering strips and other
 * native primitives where clipping and per-vertex tweaks such as
 * those in t_dd_tritmp.h are not required.
 *
 * Produces code for both inline triangles and indexed triangles.
 * Where various primitive types are unaccelerated by hardware, the
 * code attempts to fallback to other primitive types (quadstrips to
 * tristrips, lineloops to linestrips), or to indexed vertices.
 */

#if !defined(HAVE_TRIANGLES)
#error "must have at least triangles to use render template"
#endif

#if !HAVE_ELTS
#define ELTS_VARS(buf)
#define ALLOC_ELTS(nr) 0
#define EMIT_ELT( offset, elt )
#define EMIT_TWO_ELTS( offset, elt0, elt1 )
#define INCR_ELTS( nr )
#define ELT_INIT(prim)
#define GET_CURRENT_VB_MAX_ELTS() 0
#define GET_SUBSEQUENT_VB_MAX_ELTS() 0
#define RELEASE_ELT_VERTS()
#define EMIT_INDEXED_VERTS( ctx, start, count )
#endif

#ifndef EMIT_TWO_ELTS
#define EMIT_TWO_ELTS( offset, elt0, elt1 )	\
do { 						\
   EMIT_ELT( offset, elt0 ); 			\
   EMIT_ELT( offset+1, elt1 ); 			\
} while (0)
#endif


/**********************************************************************/
/*                  Render whole begin/end objects                    */
/**********************************************************************/




#if (HAVE_ELTS)
static void *TAG(emit_elts)( GLcontext *ctx, GLuint *elts, GLuint nr,
			     void *buf)
{
   GLint i;
   LOCAL_VARS;
   ELTS_VARS(buf);

   for ( i = 0 ; i+1 < nr ; i+=2, elts += 2 ) {
      EMIT_TWO_ELTS( 0, elts[0], elts[1] );
      INCR_ELTS( 2 );
   }
   
   if (i < nr) {
      EMIT_ELT( 0, elts[0] );
      INCR_ELTS( 1 );
   }

   return (void *)ELTPTR;
}
#endif

static __inline void *TAG(emit_verts)( GLcontext *ctx, GLuint start, 
				     GLuint count, void *buf )
{
   return EMIT_VERTS(ctx, start, count, buf);
}

/***********************************************************************
 *                    Render non-indexed primitives.
 ***********************************************************************/

static void TAG(render_points_verts)( GLcontext *ctx,
				      GLuint start,
				      GLuint count,
				      GLuint flags )
{
   if (HAVE_POINTS) {
      LOCAL_VARS;
      int dmasz = GET_SUBSEQUENT_VB_MAX_VERTS();
      int currentsz;
      GLuint j, nr;

      INIT( GL_POINTS );

      currentsz = GET_CURRENT_VB_MAX_VERTS();
      if (currentsz < 8)
	 currentsz = dmasz;

      for (j = start; j < count; j += nr ) {
	 nr = MIN2( currentsz, count - j );
	 TAG(emit_verts)( ctx, j, nr, ALLOC_VERTS(nr) );
	 currentsz = dmasz;
      }

   } else {
      fprintf(stderr, "%s - cannot draw primitive\n", __FUNCTION__);
      return;
   }
}

static void TAG(render_lines_verts)( GLcontext *ctx,
				     GLuint start,
				     GLuint count,
				     GLuint flags )
{
   if (HAVE_LINES) {
      LOCAL_VARS;
      int dmasz = GET_SUBSEQUENT_VB_MAX_VERTS();
      int currentsz;
      GLuint j, nr;

      INIT( GL_LINES );

      /* Emit whole number of lines in total and in each buffer:
       */
      count -= (count-start) & 1;
      currentsz = GET_CURRENT_VB_MAX_VERTS();
      currentsz -= currentsz & 1;
      dmasz -= dmasz & 1;

      if (currentsz < 8)
	 currentsz = dmasz;

      for (j = start; j < count; j += nr ) {
	 nr = MIN2( currentsz, count - j );
	 TAG(emit_verts)( ctx, j, nr, ALLOC_VERTS(nr) );
	 currentsz = dmasz;
      }

   } else {
      fprintf(stderr, "%s - cannot draw primitive\n", __FUNCTION__);
      return;
   }
}


static void TAG(render_line_strip_verts)( GLcontext *ctx,
					  GLuint start,
					  GLuint count,
					  GLuint flags )
{
   if (HAVE_LINE_STRIPS) {
      LOCAL_VARS;
      int dmasz = GET_SUBSEQUENT_VB_MAX_VERTS();
      int currentsz;
      GLuint j, nr;

      INIT( GL_LINE_STRIP );

      currentsz = GET_CURRENT_VB_MAX_VERTS();
      if (currentsz < 8)
	 currentsz = dmasz;

      for (j = start; j + 1 < count; j += nr - 1 ) {
	 nr = MIN2( currentsz, count - j );
	 TAG(emit_verts)( ctx, j, nr, ALLOC_VERTS(nr) );
	 currentsz = dmasz;
      }
 
      FLUSH();

   } else {
      fprintf(stderr, "%s - cannot draw primitive\n", __FUNCTION__);
      return;
   }
}


static void TAG(render_line_loop_verts)( GLcontext *ctx,
					 GLuint start,
					 GLuint count,
					 GLuint flags )
{
   if (HAVE_LINE_STRIPS) {
      LOCAL_VARS;
      int dmasz = GET_SUBSEQUENT_VB_MAX_VERTS();
      int currentsz;
      GLuint j, nr;

      INIT( GL_LINE_STRIP );

      if (flags & PRIM_BEGIN)
	 j = start;
      else
	 j = start + 1;

      /* Ensure last vertex won't wrap buffers:
       */
      currentsz = GET_CURRENT_VB_MAX_VERTS();
      currentsz--;
      dmasz--;

      if (currentsz < 8) {
	 currentsz = dmasz;
      }

      if (j + 1 < count) {
	 for ( ; j + 1 < count; j += nr - 1 ) {
	    nr = MIN2( currentsz, count - j );

	    if (j + nr >= count &&
		start < count - 1 && 
		(flags & PRIM_END)) 
	    {
	       void *tmp;
	       tmp = ALLOC_VERTS(nr+1);
	       tmp = TAG(emit_verts)( ctx, j, nr, tmp );
	       tmp = TAG(emit_verts)( ctx, start, 1, tmp );
	    }
	    else {
	       TAG(emit_verts)( ctx, j, nr, ALLOC_VERTS(nr) );
	       currentsz = dmasz;
	    }
	 }

      }
      else if (start + 1 < count && (flags & PRIM_END)) {
	 void *tmp;
	 tmp = ALLOC_VERTS(2);
	 tmp = TAG(emit_verts)( ctx, start+1, 1, tmp );
	 tmp = TAG(emit_verts)( ctx, start, 1, tmp );
      }

      FLUSH();

   } else {
      fprintf(stderr, "%s - cannot draw primitive\n", __FUNCTION__);
      return;
   }
}


static void TAG(render_triangles_verts)( GLcontext *ctx,
					 GLuint start,
					 GLuint count,
					 GLuint flags )
{
   LOCAL_VARS;
   int dmasz = (GET_SUBSEQUENT_VB_MAX_VERTS()/3) * 3;
   int currentsz;
   GLuint j, nr;

   INIT(GL_TRIANGLES);

   currentsz = (GET_CURRENT_VB_MAX_VERTS()/3) * 3;

   /* Emit whole number of tris in total.  dmasz is already a multiple
    * of 3.
    */
   count -= (count-start)%3;

   if (currentsz < 8)
      currentsz = dmasz;

   for (j = start; j < count; j += nr) {
      nr = MIN2( currentsz, count - j );
      TAG(emit_verts)( ctx, j, nr, ALLOC_VERTS(nr) );
      currentsz = dmasz;
   }
}



static void TAG(render_tri_strip_verts)( GLcontext *ctx,
					 GLuint start,
					 GLuint count,
					 GLuint flags )
{
   if (HAVE_TRI_STRIPS) {
      LOCAL_VARS;
      GLuint j, nr;
      int dmasz = GET_SUBSEQUENT_VB_MAX_VERTS();
      int currentsz;

      INIT(GL_TRIANGLE_STRIP);

      currentsz = GET_CURRENT_VB_MAX_VERTS();

      if (currentsz < 8) {
	 currentsz = dmasz;
      }

      /* From here on emit even numbers of tris when wrapping over buffers:
       */
      dmasz -= (dmasz & 1);
      currentsz -= (currentsz & 1);

      for (j = start ; j + 2 < count; j += nr - 2 ) {
	 nr = MIN2( currentsz, count - j );
	 TAG(emit_verts)( ctx, j, nr, ALLOC_VERTS(nr) );
	 currentsz = dmasz;
      }

      FLUSH();

   } else {
      fprintf(stderr, "%s - cannot draw primitive\n", __FUNCTION__);
      return;
   }
}

static void TAG(render_tri_fan_verts)( GLcontext *ctx,
				       GLuint start,
				       GLuint count,
				       GLuint flags )
{
   if (HAVE_TRI_FANS) {
      LOCAL_VARS;
      GLuint j, nr;
      int dmasz = GET_SUBSEQUENT_VB_MAX_VERTS();
      int currentsz;

      INIT(GL_TRIANGLE_FAN);

      currentsz = GET_CURRENT_VB_MAX_VERTS();
      if (currentsz < 8) {
	 currentsz = dmasz;
      }

      for (j = start + 1 ; j + 1 < count; j += nr - 2 ) {
	 void *tmp;
	 nr = MIN2( currentsz, count - j + 1 );
	 tmp = ALLOC_VERTS( nr );
	 tmp = TAG(emit_verts)( ctx, start, 1, tmp );
	 tmp = TAG(emit_verts)( ctx, j, nr - 1, tmp );
	 currentsz = dmasz;
      }

      FLUSH();
   }
   else {
      /* Could write code to emit these as indexed vertices (for the
       * g400, for instance).
       */
      fprintf(stderr, "%s - cannot draw primitive\n", __FUNCTION__);
      return;
   }
}


static void TAG(render_poly_verts)( GLcontext *ctx,
				    GLuint start,
				    GLuint count,
				    GLuint flags )
{
   if (HAVE_POLYGONS) {
      LOCAL_VARS;
      GLuint j, nr;
      int dmasz = GET_SUBSEQUENT_VB_MAX_VERTS();
      int currentsz;

      INIT(GL_POLYGON);

      currentsz = GET_CURRENT_VB_MAX_VERTS();
      if (currentsz < 8) {
	 currentsz = dmasz;
      }

      for (j = start + 1 ; j + 1 < count ; j += nr - 2 ) {
	 void *tmp;
	 nr = MIN2( currentsz, count - j + 1 );
	 tmp = ALLOC_VERTS( nr );
	 tmp = TAG(emit_verts)( ctx, start, 1, tmp );
	 tmp = TAG(emit_verts)( ctx, j, nr - 1, tmp );
	 currentsz = dmasz;
      }

      FLUSH();
   }
   else if (HAVE_TRI_FANS && !(ctx->_TriangleCaps & DD_FLATSHADE)) {
      TAG(render_tri_fan_verts)( ctx, start, count, flags );
   } else {
      fprintf(stderr, "%s - cannot draw primitive\n", __FUNCTION__);
      return;
   }
}

static void TAG(render_quad_strip_verts)( GLcontext *ctx,
					  GLuint start,
					  GLuint count,
					  GLuint flags )
{
   GLuint j, nr;

   if (HAVE_QUAD_STRIPS) {
      LOCAL_VARS;