3 * Mesa 3-D graphics library
5 * Copyright (C) 1999-2006 Brian Paul All Rights Reserved.
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:
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
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 OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
21 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23 * OTHER DEALINGS IN THE SOFTWARE.
26 * Keith Whitwell <keithw@vmware.com>
29 /* Helper for drivers which find themselves rendering a range of
30 * indices starting somewhere above zero. Typically the application
31 * is issuing multiple DrawArrays() or DrawElements() to draw
32 * successive primitives layed out linearly in the vertex arrays.
33 * Unless the vertex arrays are all in a VBO, the OpenGL semantics
34 * imply that we need to re-upload the vertex data on each draw call.
35 * In that case, we want to avoid starting the upload at zero, as it
36 * will mean every draw call uploads an increasing amount of not-used
37 * vertex data. Worse - in the software tnl module, all those
38 * vertices will be transformed and lit.
40 * If we just upload the new data, however, the indices will be
41 * incorrect as we tend to upload each set of vertex data to a new
44 * This file provides a helper to adjust the arrays, primitives and
45 * indices of a draw call so that it can be re-issued with a min_index
49 #include "main/glheader.h"
50 #include "main/imports.h"
51 #include "main/mtypes.h"
56 #define REBASE(TYPE) \
57 static void *rebase_##TYPE( const void *ptr, \
62 const TYPE *in = (TYPE *)ptr; \
63 TYPE *tmp_indices = malloc(count * sizeof(TYPE)); \
65 if (tmp_indices == NULL) { \
66 _mesa_error_no_memory(__func__); \
70 for (i = 0; i < count; i++) \
71 tmp_indices[i] = in[i] - min_index; \
73 return (void *)tmp_indices; \
81 GLboolean
vbo_all_varyings_in_vbos( const struct gl_client_array
*arrays
[] )
85 for (i
= 0; i
< VERT_ATTRIB_MAX
; i
++)
86 if (arrays
[i
]->StrideB
&&
87 arrays
[i
]->BufferObj
->Name
== 0)
93 GLboolean
vbo_any_varyings_in_vbos( const struct gl_client_array
*arrays
[] )
97 for (i
= 0; i
< VERT_ATTRIB_MAX
; i
++)
98 if (arrays
[i
]->BufferObj
->Name
!= 0)
104 /* Adjust primitives, indices and vertex definitions so that min_index
105 * becomes zero. There are lots of reasons for wanting to do this, eg:
108 * - any time min_index != 0, otherwise unused vertices lower than
109 * min_index will be transformed.
112 * - if ib != NULL and min_index != 0, otherwise vertices lower than
113 * min_index will be uploaded. Requires adjusting index values.
115 * - if ib == NULL and min_index != 0, just for convenience so this doesn't
116 * have to be handled within the driver.
118 * Hardware tnl with VBO support:
119 * - as above, but only when vertices are not (all?) in VBO's.
120 * - can't save time by trying to upload half a vbo - typically it is
123 void vbo_rebase_prims( struct gl_context
*ctx
,
124 const struct gl_client_array
*arrays
[],
125 const struct _mesa_prim
*prim
,
127 const struct _mesa_index_buffer
*ib
,
132 struct gl_client_array tmp_arrays
[VERT_ATTRIB_MAX
];
133 const struct gl_client_array
*tmp_array_pointers
[VERT_ATTRIB_MAX
];
135 struct _mesa_index_buffer tmp_ib
;
136 struct _mesa_prim
*tmp_prims
= NULL
;
137 const struct gl_client_array
**saved_arrays
= ctx
->Array
._DrawArrays
;
138 void *tmp_indices
= NULL
;
141 assert(min_index
!= 0);
144 printf("%s %d..%d\n", __FUNCTION__
, min_index
, max_index
);
147 /* XXX this path is disabled for now.
148 * There's rendering corruption in some apps when it's enabled.
150 if (0 && ib
&& ctx
->Extensions
.ARB_draw_elements_base_vertex
) {
151 /* If we can just tell the hardware or the TNL to interpret our
152 * indices with a different base, do so.
154 tmp_prims
= malloc(sizeof(*prim
) * nr_prims
);
156 if (tmp_prims
== NULL
) {
157 _mesa_error_no_memory(__func__
);
161 for (i
= 0; i
< nr_prims
; i
++) {
162 tmp_prims
[i
] = prim
[i
];
163 tmp_prims
[i
].basevertex
-= min_index
;
168 /* Unfortunately need to adjust each index individually.
170 GLboolean map_ib
= ib
->obj
->Name
&&
171 !ib
->obj
->Mappings
[MAP_INTERNAL
].Pointer
;
175 ctx
->Driver
.MapBufferRange(ctx
, 0, ib
->obj
->Size
, GL_MAP_READ_BIT
,
176 ib
->obj
, MAP_INTERNAL
);
179 ptr
= ADD_POINTERS(ib
->obj
->Mappings
[MAP_INTERNAL
].Pointer
, ib
->ptr
);
181 /* Some users might prefer it if we translated elements to
182 * GLuints here. Others wouldn't...
185 case GL_UNSIGNED_INT
:
186 tmp_indices
= rebase_GLuint( ptr
, ib
->count
, min_index
);
188 case GL_UNSIGNED_SHORT
:
189 tmp_indices
= rebase_GLushort( ptr
, ib
->count
, min_index
);
191 case GL_UNSIGNED_BYTE
:
192 tmp_indices
= rebase_GLubyte( ptr
, ib
->count
, min_index
);
197 ctx
->Driver
.UnmapBuffer(ctx
, ib
->obj
, MAP_INTERNAL
);
199 if (tmp_indices
== NULL
) {
203 tmp_ib
.obj
= ctx
->Shared
->NullBufferObj
;
204 tmp_ib
.ptr
= tmp_indices
;
205 tmp_ib
.count
= ib
->count
;
206 tmp_ib
.type
= ib
->type
;
211 /* Otherwise the primitives need adjustment.
213 tmp_prims
= malloc(sizeof(*prim
) * nr_prims
);
215 if (tmp_prims
== NULL
) {
216 _mesa_error_no_memory(__func__
);
220 for (i
= 0; i
< nr_prims
; i
++) {
221 /* If this fails, it could indicate an application error:
223 assert(prim
[i
].start
>= min_index
);
225 tmp_prims
[i
] = prim
[i
];
226 tmp_prims
[i
].start
-= min_index
;
232 /* Just need to adjust the pointer values on each incoming array.
233 * This works for VBO and non-vbo rendering and shouldn't pesimize
234 * VBO-based upload schemes. However this may still not be a fast
235 * path for hardware tnl for VBO based rendering as most machines
236 * will be happier if you just specify a starting vertex value in
239 * For drivers with hardware tnl, you only want to do this if you
240 * are forced to, eg non-VBO indexed rendering with start != 0.
242 for (i
= 0; i
< VERT_ATTRIB_MAX
; i
++) {
243 tmp_arrays
[i
] = *arrays
[i
];
244 tmp_arrays
[i
].Ptr
+= min_index
* tmp_arrays
[i
].StrideB
;
245 tmp_array_pointers
[i
] = &tmp_arrays
[i
];
248 /* Re-issue the draw call.
250 ctx
->Array
._DrawArrays
= tmp_array_pointers
;
251 ctx
->NewDriverState
|= ctx
->DriverFlags
.NewArray
;
259 max_index
- min_index
,
262 ctx
->Array
._DrawArrays
= saved_arrays
;
263 ctx
->NewDriverState
|= ctx
->DriverFlags
.NewArray
;