1 /*
2  * mesa 3-D graphics library
3  * Version:  6.5
4  *
5  * Copyright (C) 1999-2006  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  * \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 "main/mfeatures.h"
55 #include "vbo.h"
56 #include "vbo_attrib.h"
57 #include "vbo_exec.h"
58 #include "vbo_save.h"
59 
60 
61 /** Used to signal when transitioning from one kind of drawing method
62  * to another.
63  */
64 enum draw_method
65 {
66    DRAW_NONE,          /**< Initial value only */
67    DRAW_BEGIN_END,
68    DRAW_DISPLAY_LIST,
69    DRAW_ARRAYS
70 };
71 
72 
73 struct vbo_context {
74    struct gl_client_array currval[VBO_ATTRIB_MAX];
75 
76    /** Map VERT_ATTRIB_x to VBO_ATTRIB_y */
77    GLuint map_vp_none[VERT_ATTRIB_MAX];
78    GLuint map_vp_arb[VERT_ATTRIB_MAX];
79 
80    struct vbo_exec_context exec;
81 #if FEATURE_dlist
82    struct vbo_save_context save;
83 #endif
84 
85    /* Callback into the driver.  This must always succeed, the driver
86     * is responsible for initiating any fallback actions required:
87     */
88    vbo_draw_func draw_prims;
89 
90    enum draw_method last_draw_method;
91 };
92 
93 
vbo_context(struct gl_context * ctx)94 static inline struct vbo_context *vbo_context(struct gl_context *ctx)
95 {
96    return (struct vbo_context *)(ctx->swtnl_im);
97 }
98 
99 
100 /**
101  * Return VP_x token to indicate whether we're running fixed-function
102  * vertex transformation, an NV vertex program or ARB vertex program/shader.
103  */
104 static inline enum vp_mode
get_program_mode(struct gl_context * ctx)105 get_program_mode( struct gl_context *ctx )
106 {
107    if (!ctx->VertexProgram._Current)
108       return VP_NONE;
109    else if (ctx->VertexProgram._Current == ctx->VertexProgram._TnlProgram)
110       return VP_NONE;
111    else if (ctx->VertexProgram._Current->IsNVProgram)
112       return VP_NV;
113    else
114       return VP_ARB;
115 }
116 
117 
118 /**
119  * This is called by glBegin, glDrawArrays and glDrawElements (and
120  * variations of those calls).  When we transition from immediate mode
121  * drawing to array drawing we need to invalidate the array state.
122  *
123  * glBegin/End builds vertex arrays.  Those arrays may look identical
124  * to glDrawArrays arrays except that the position of the elements may
125  * be different.  For example, arrays of (position3v, normal3f) vs. arrays
126  * of (normal3f, position3f).  So we need to make sure we notify drivers
127  * that arrays may be changing.
128  */
129 static inline void
vbo_draw_method(struct vbo_context * vbo,enum draw_method method)130 vbo_draw_method(struct vbo_context *vbo, enum draw_method method)
131 {
132    if (vbo->last_draw_method != method) {
133       struct gl_context *ctx = vbo->exec.ctx;
134 
135       switch (method) {
136       case DRAW_ARRAYS:
137          ctx->Array._DrawArrays = vbo->exec.array.inputs;
138          break;
139       case DRAW_BEGIN_END:
140          ctx->Array._DrawArrays = vbo->exec.vtx.inputs;
141          break;
142       case DRAW_DISPLAY_LIST:
143          ctx->Array._DrawArrays = vbo->save.inputs;
144          break;
145       default:
146          ASSERT(0);
147       }
148 
149       ctx->NewDriverState |= ctx->DriverFlags.NewArray;
150       vbo->last_draw_method = method;
151    }
152 }
153 
154 /**
155  * Return if format is integer. The immediate mode commands only emit floats
156  * for non-integer types, thus everything else is integer.
157  */
158 static inline GLboolean
vbo_attrtype_to_integer_flag(GLenum format)159 vbo_attrtype_to_integer_flag(GLenum format)
160 {
161    switch (format) {
162    case GL_FLOAT:
163       return GL_FALSE;
164    case GL_INT:
165    case GL_UNSIGNED_INT:
166       return GL_TRUE;
167    default:
168       ASSERT(0);
169       return GL_FALSE;
170    }
171 }
172 
173 
174 /**
175  * Return default component values for the given format.
176  * The return type is an array of floats, because that's how we declare
177  * the vertex storage despite the fact we sometimes store integers in there.
178  */
179 static inline const GLfloat *
vbo_get_default_vals_as_float(GLenum format)180 vbo_get_default_vals_as_float(GLenum format)
181 {
182    static const GLfloat default_float[4] = { 0, 0, 0, 1 };
183    static const GLint default_int[4] = { 0, 0, 0, 1 };
184 
185    switch (format) {
186    case GL_FLOAT:
187       return default_float;
188    case GL_INT:
189    case GL_UNSIGNED_INT:
190       return (const GLfloat*)default_int;
191    default:
192       ASSERT(0);
193       return NULL;
194    }
195 }
196 
197 #endif
198