src/mesa/vbo/vbo_exec.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  6.3
   4  *
   5  * Copyright (C) 1999-2005  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  * THE AUTHORS 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  * Authors:
  25  *    Keith Whitwell <keith@tungstengraphics.com>
  26  */
  27
  28
  29 #include "main/api_arrayelt.h"
  30 #include "main/glheader.h"
  31 #include "main/mtypes.h"
  32 #include "main/vtxfmt.h"
  33 #include "vbo_context.h"
  34
  35
  36
  37 void vbo_exec_init( struct gl_context *ctx )
  38 {
  39    struct vbo_exec_context *exec = &vbo_context(ctx)->exec;
  40
  41    exec->ctx = ctx;
  42
  43    /* Initialize the arrayelt helper
  44     */
  45    if (!ctx->aelt_context &&
  46        !_ae_create_context( ctx ))
  47       return;
  48
  49    vbo_exec_vtx_init( exec );
  50    vbo_exec_array_init( exec );
  51
  52    ctx->Driver.NeedFlush = 0;
  53    ctx->Driver.CurrentExecPrimitive = PRIM_OUTSIDE_BEGIN_END;
  54    ctx->Driver.BeginVertices = vbo_exec_BeginVertices;
  55    ctx->Driver.FlushVertices = vbo_exec_FlushVertices;
  56
  57    vbo_exec_invalidate_state( ctx, ~0 );
  58 }
  59
  60
  61 void vbo_exec_destroy( struct gl_context *ctx )
  62 {
  63    struct vbo_exec_context *exec = &vbo_context(ctx)->exec;
  64
  65    if (ctx->aelt_context) {
  66       _ae_destroy_context( ctx );
  67       ctx->aelt_context = NULL;
  68    }
  69
  70    vbo_exec_vtx_destroy( exec );
  71    vbo_exec_array_destroy( exec );
  72 }
  73
  74
  75 /**
  76  * Really want to install these callbacks to a central facility to be
  77  * invoked according to the state flags.  That will have to wait for a
  78  * mesa rework:
  79  */
  80 void vbo_exec_invalidate_state( struct gl_context *ctx, GLuint new_state )
  81 {
  82    struct vbo_exec_context *exec = &vbo_context(ctx)->exec;
  83
  84    if (new_state & (_NEW_PROGRAM|_NEW_ARRAY)) {
  85       exec->array.recalculate_inputs = GL_TRUE;
  86    }
  87
  88    if (new_state & _NEW_EVAL)
  89       exec->eval.recalculate_maps = 1;
  90
  91    _ae_invalidate_state(ctx, new_state);
  92 }
  93
  94
  95 /**
  96  * Figure out the number of transform feedback primitives that will be output
  97  * considering the drawing mode, number of vertices, and instance count,
  98  * assuming that no geometry shading is done and primitive restart is not
  99  * used.
 100  *
 101  * This is used by driver back-ends in implementing the PRIMITIVES_GENERATED
 102  * and TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN queries.  It is also used to
 103  * pre-validate draw calls in GLES3 (where draw calls only succeed if there is
 104  * enough room in the transform feedback buffer for the result).
 105  */
 106 size_t
 107 vbo_count_tessellated_primitives(GLenum mode, GLuint count,
 108                                  GLuint num_instances)
 109 {
 110    size_t num_primitives;
 111    switch (mode) {
 112    case GL_POINTS:
 113       num_primitives = count;
 114       break;
 115    case GL_LINE_STRIP:
 116       num_primitives = count >= 2 ? count - 1 : 0;
 117       break;
 118    case GL_LINE_LOOP:
 119       num_primitives = count >= 2 ? count : 0;
 120       break;
 121    case GL_LINES:
 122       num_primitives = count / 2;
 123       break;
 124    case GL_TRIANGLE_STRIP:
 125    case GL_TRIANGLE_FAN:
 126    case GL_POLYGON:
 127       num_primitives = count >= 3 ? count - 2 : 0;
 128       break;
 129    case GL_TRIANGLES:
 130       num_primitives = count / 3;
 131       break;
 132    case GL_QUAD_STRIP:
 133       num_primitives = count >= 4 ? ((count / 2) - 1) * 2 : 0;
 134       break;
 135    case GL_QUADS:
 136       num_primitives = (count / 4) * 2;
 137       break;
 138    default:
 139       assert(!"Unexpected primitive type in count_tessellated_primitives");
 140       num_primitives = 0;
 141       break;
 142    }
 143    return num_primitives * num_instances;
 144 }