src/mesa/vbo/vbo_context.h

   1 /*
   2  * mesa 3-D graphics library
   3  *
   4  * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the "Software"),
   8  * to deal in the Software without restriction, including without limitation
   9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10  * and/or sell copies of the Software, and to permit persons to whom the
  11  * Software is furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included
  14  * in all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  22  * OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 /**
  26  * \file vbo_context.h
  27  * \brief VBO builder module datatypes and definitions.
  28  * \author Keith Whitwell
  29  */
  30
  31
  32 /**
  33  * \mainpage The VBO builder module
  34  *
  35  * This module hooks into the GL dispatch table and catches all vertex
  36  * building and drawing commands, such as glVertex3f, glBegin and
  37  * glDrawArrays.  The module stores all incoming vertex data as arrays
  38  * in GL vertex buffer objects (VBOs), and translates all drawing
  39  * commands into calls to a driver supplied DrawPrimitives() callback.
  40  *
  41  * The module captures both immediate mode and display list drawing,
  42  * and manages the allocation, reference counting and deallocation of
  43  * vertex buffer objects itself.
  44  *
  45  * The DrawPrimitives() callback can be either implemented by the
  46  * driver itself or hooked to the tnl module's _tnl_draw_primitives()
  47  * function for hardware without tnl capablilties or during fallbacks.
  48  */
  49
  50
  51 #ifndef _VBO_CONTEXT_H
  52 #define _VBO_CONTEXT_H
  53
  54 #include "vbo.h"
  55 #include "vbo_attrib.h"
  56 #include "vbo_exec.h"
  57 #include "vbo_save.h"
  58
  59
  60 /** Used to signal when transitioning from one kind of drawing method
  61  * to another.
  62  */
  63 enum draw_method
  64 {
  65    DRAW_NONE,          /**< Initial value only */
  66    DRAW_BEGIN_END,
  67    DRAW_DISPLAY_LIST,
  68    DRAW_ARRAYS
  69 };
  70
  71
  72 struct vbo_context {
  73    struct gl_client_array currval[VBO_ATTRIB_MAX];
  74
  75    /** Map VERT_ATTRIB_x to VBO_ATTRIB_y */
  76    GLuint map_vp_none[VERT_ATTRIB_MAX];
  77    GLuint map_vp_arb[VERT_ATTRIB_MAX];
  78
  79    struct vbo_exec_context exec;
  80    struct vbo_save_context save;
  81
  82    /* Callback into the driver.  This must always succeed, the driver
  83     * is responsible for initiating any fallback actions required:
  84     */
  85    vbo_draw_func draw_prims;
  86
  87    enum draw_method last_draw_method;
  88 };
  89
  90
  91 static inline struct vbo_context *vbo_context(struct gl_context *ctx)
  92 {
  93    return ctx->vbo_context;
  94 }
  95
  96
  97 /**
  98  * Return VP_x token to indicate whether we're running fixed-function
  99  * vertex transformation, an NV vertex program or ARB vertex program/shader.
 100  */
 101 static inline enum vp_mode
 102 get_program_mode( struct gl_context *ctx )
 103 {
 104    if (!ctx->VertexProgram._Current)
 105       return VP_NONE;
 106    else if (ctx->VertexProgram._Current == ctx->VertexProgram._TnlProgram)
 107       return VP_NONE;
 108    else
 109       return VP_ARB;
 110 }
 111
 112
 113 /**
 114  * This is called by glBegin, glDrawArrays and glDrawElements (and
 115  * variations of those calls).  When we transition from immediate mode
 116  * drawing to array drawing we need to invalidate the array state.
 117  *
 118  * glBegin/End builds vertex arrays.  Those arrays may look identical
 119  * to glDrawArrays arrays except that the position of the elements may
 120  * be different.  For example, arrays of (position3v, normal3f) vs. arrays
 121  * of (normal3f, position3f).  So we need to make sure we notify drivers
 122  * that arrays may be changing.
 123  */
 124 static inline void
 125 vbo_draw_method(struct vbo_context *vbo, enum draw_method method)
 126 {
 127    if (vbo->last_draw_method != method) {
 128       struct gl_context *ctx = vbo->exec.ctx;
 129
 130       switch (method) {
 131       case DRAW_ARRAYS:
 132          ctx->Array._DrawArrays = vbo->exec.array.inputs;
 133          break;
 134       case DRAW_BEGIN_END:
 135          ctx->Array._DrawArrays = vbo->exec.vtx.inputs;
 136          break;
 137       case DRAW_DISPLAY_LIST:
 138          ctx->Array._DrawArrays = vbo->save.inputs;
 139          break;
 140       default:
 141          ASSERT(0);
 142       }
 143
 144       ctx->NewDriverState |= ctx->DriverFlags.NewArray;
 145       vbo->last_draw_method = method;
 146    }
 147 }
 148
 149 /**
 150  * Return if format is integer. The immediate mode commands only emit floats
 151  * for non-integer types, thus everything else is integer.
 152  */
 153 static inline GLboolean
 154 vbo_attrtype_to_integer_flag(GLenum format)
 155 {
 156    switch (format) {
 157    case GL_FLOAT:
 158       return GL_FALSE;
 159    case GL_INT:
 160    case GL_UNSIGNED_INT:
 161       return GL_TRUE;
 162    default:
 163       ASSERT(0);
 164       return GL_FALSE;
 165    }
 166 }
 167
 168
 169 /**
 170  * Return default component values for the given format.
 171  * The return type is an array of floats, because that's how we declare
 172  * the vertex storage despite the fact we sometimes store integers in there.
 173  */
 174 static inline const GLfloat *
 175 vbo_get_default_vals_as_float(GLenum format)
 176 {
 177    static const GLfloat default_float[4] = { 0, 0, 0, 1 };
 178    static const GLint default_int[4] = { 0, 0, 0, 1 };
 179
 180    switch (format) {
 181    case GL_FLOAT:
 182       return default_float;
 183    case GL_INT:
 184    case GL_UNSIGNED_INT:
 185       return (const GLfloat*)default_int;
 186    default:
 187       ASSERT(0);
 188       return NULL;
 189    }
 190 }
 191
 192 #endif