/*
* Mesa 3-D graphics library
*
* Copyright (C) 1999-2008 Brian Paul All Rights Reserved.
* Copyright (C) 2009 VMware, Inc. 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
* THE AUTHORS OR COPYRIGHT HOLDERS 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.
*/
/**
* \file
* \brief Extension handling
*/
#include "glheader.h"
#include "imports.h"
#include "context.h"
#include "extensions.h"
#include "macros.h"
#include "mtypes.h"
struct gl_extensions _mesa_extension_override_enables;
struct gl_extensions _mesa_extension_override_disables;
static char *extra_extensions = NULL;
/**
* Given a member \c x of struct gl_extensions, return offset of
* \c x in bytes.
*/
#define o(x) offsetof(struct gl_extensions, x)
static bool disabled_extensions[MESA_EXTENSION_COUNT];
/**
* Given an extension name, lookup up the corresponding member of struct
* gl_extensions and return that member's index. If the name is
* not found in the \c _mesa_extension_table, return -1.
*
* \param name Name of extension.
* \return Index of member in struct gl_extensions.
*/
static int
name_to_index(const char* name)
{
unsigned i;
if (name == 0)
return -1;
for (i = 0; i < MESA_EXTENSION_COUNT; ++i) {
if (strcmp(name, _mesa_extension_table[i].name) == 0)
return i;
}
return -1;
}
/**
* Overrides extensions in \c ctx based on the values in
* _mesa_extension_override_enables and _mesa_extension_override_disables.
*/
static void
override_extensions_in_context(struct gl_context *ctx)
{
unsigned i;
const GLboolean *enables =
(GLboolean*) &_mesa_extension_override_enables;
const GLboolean *disables =
(GLboolean*) &_mesa_extension_override_disables;
GLboolean *ctx_ext = (GLboolean*)&ctx->Extensions;
for (i = 0; i < MESA_EXTENSION_COUNT; ++i) {
size_t offset = _mesa_extension_table[i].offset;
assert(!enables[offset] || !disables[offset]);
if (enables[offset]) {
ctx_ext[offset] = 1;
} else if (disables[offset]) {
ctx_ext[offset] = 0;
}
}
}
/**
* Enable all extensions suitable for a software-only renderer.
* This is a convenience function used by the XMesa, OSMesa, GGI drivers, etc.
*/
void
_mesa_enable_sw_extensions(struct gl_context *ctx)
{
ctx->Extensions.ARB_depth_clamp = GL_TRUE;
ctx->Extensions.ARB_depth_texture = GL_TRUE;
ctx->Extensions.ARB_draw_elements_base_vertex = GL_TRUE;
ctx->Extensions.ARB_draw_instanced = GL_TRUE;
ctx->Extensions.ARB_explicit_attrib_location = GL_TRUE;
ctx->Extensions.ARB_fragment_coord_conventions = GL_TRUE;
ctx->Extensions.ARB_fragment_program = GL_TRUE;
ctx->Extensions.ARB_fragment_program_shadow = GL_TRUE;
ctx->Extensions.ARB_fragment_shader = GL_TRUE;
ctx->Extensions.ARB_framebuffer_object = GL_TRUE;
ctx->Extensions.ARB_half_float_vertex = GL_TRUE;
ctx->Extensions.ARB_map_buffer_range = GL_TRUE;
ctx->Extensions.ARB_occlusion_query = GL_TRUE;
ctx->Extensions.ARB_occlusion_query2 = GL_TRUE;
ctx->Extensions.ARB_point_sprite = GL_TRUE;
ctx->Extensions.ARB_shadow = GL_TRUE;
ctx->Extensions.ARB_texture_border_clamp = GL_TRUE;
ctx->Extensions.ARB_texture_compression_bptc = GL_TRUE;
ctx->Extensions.ARB_texture_cube_map = GL_TRUE;
ctx->Extensions.ARB_texture_env_combine = GL_TRUE;
ctx->Extensions.ARB_texture_env_crossbar = GL_TRUE;
ctx->Extensions.ARB_texture_env_dot3 = GL_TRUE;
#ifdef TEXTURE_FLOAT_ENABLED
ctx->Extensions.ARB_texture_float = GL_TRUE;
#endif
ctx->Extensions.ARB_texture_mirror_clamp_to_edge = GL_TRUE;
ctx->Extensions.ARB_texture_non_power_of_two = GL_TRUE;
ctx->Extensions.ARB_texture_rg = GL_TRUE;
ctx->Extensions.ARB_texture_compression_rgtc = GL_TRUE;
ctx->Extensions.ARB_vertex_program = GL_TRUE;
ctx->Extensions.ARB_vertex_shader = GL_TRUE;
ctx->Extensions.ARB_sync = GL_TRUE;
ctx->Extensions.APPLE_object_purgeable = GL_TRUE;
ctx->Extensions.ATI_fragment_shader = GL_TRUE;
ctx->Extensions.ATI_texture_compression_3dc = GL_TRUE;
ctx->Extensions.ATI_texture_env_combine3 = GL_TRUE;
ctx->Extensions.ATI_texture_mirror_once = GL_TRUE;
ctx->Extensions.ATI_separate_stencil = GL_TRUE;
ctx->Extensions.EXT_blend_color = GL_TRUE;
ctx->Extensions.EXT_blend_equation_separate = GL_TRUE;
ctx->Extensions.EXT_blend_func_separate = GL_TRUE;
ctx->Extensions.EXT_blend_minmax = GL_TRUE;
ctx->Extensions.EXT_depth_bounds_test = GL_TRUE;
ctx->Extensions.EXT_draw_buffers2 = GL_TRUE;
ctx->Extensions.EXT_pixel_buffer_object = GL_TRUE;
ctx->Extensions.EXT_point_parameters = GL_TRUE;
ctx->Extensions.EXT_provoking_vertex = GL_TRUE;
ctx->Extensions.EXT_stencil_two_side = GL_TRUE;
ctx->Extensions.EXT_texture_array = GL_TRUE;
ctx->Extensions.EXT_texture_compression_latc = GL_TRUE;
ctx->Extensions.EXT_texture_env_dot3 = GL_TRUE;
ctx->Extensions.EXT_texture_filter_anisotropic = GL_TRUE;
ctx->Extensions.EXT_texture_mirror_clamp = GL_TRUE;
ctx->Extensions.EXT_texture_shared_exponent = GL_TRUE;
ctx->Extensions.EXT_texture_sRGB = GL_TRUE;
ctx->Extensions.EXT_texture_sRGB_decode = GL_TRUE;
ctx->Extensions.EXT_texture_swizzle = GL_TRUE;
/*ctx->Extensions.EXT_transform_feedback = GL_TRUE;*/
ctx->Extensions.EXT_vertex_array_bgra = GL_TRUE;
ctx->Extensions.MESA_pack_invert = GL_TRUE;
ctx->Extensions.MESA_ycbcr_texture = GL_TRUE;
ctx->Extensions.NV_conditional_render = GL_TRUE;
ctx->Extensions.NV_point_sprite = GL_TRUE;
ctx->Extensions.NV_texture_env_combine4 = GL_TRUE;
ctx->Extensions.NV_texture_rectangle = GL_TRUE;
ctx->Extensions.EXT_gpu_program_parameters = GL_TRUE;
ctx->Extensions.OES_standard_derivatives = GL_TRUE;
ctx->Extensions.TDFX_texture_compression_FXT1 = GL_TRUE;
if (ctx->Mesa_DXTn) {
ctx->Extensions.ANGLE_texture_compression_dxt = GL_TRUE;
ctx->Extensions.EXT_texture_compression_s3tc = GL_TRUE;
}
}
/**
* Either enable or disable the named extension.
* \return offset of extensions withint `ext' or 0 if extension is not known
*/
static size_t
set_extension(struct gl_extensions *ext, int i, GLboolean state)
{
size_t offset;
offset = i < 0 ? 0 : _mesa_extension_table[i].offset;
if (offset != 0 && (offset != o(dummy_true) || state != GL_FALSE)) {
((GLboolean *) ext)[offset] = state;
}
return offset;
}
/**
* \brief Apply the \c MESA_EXTENSION_OVERRIDE environment variable.
*
* \c MESA_EXTENSION_OVERRIDE is a space-separated list of extensions to
* enable or disable. The list is processed thus:
* - Enable recognized extension names that are prefixed with '+'.
* - Disable recognized extension names that are prefixed with '-'.
* - Enable recognized extension names that are not prefixed.
* - Collect unrecognized extension names in a new string.
*
* \c MESA_EXTENSION_OVERRIDE was previously parsed during
* _mesa_one_time_init_extension_overrides. We just use the results of that
* parsing in this function.
*
* \return Space-separated list of unrecognized extension names (which must
* be freed). Does not return \c NULL.
*/
static char *
get_extension_override( struct gl_context *ctx )
{
override_extensions_in_context(ctx);
if (extra_extensions == NULL) {
return calloc(1, sizeof(char));
} else {
_mesa_problem(ctx, "Trying to enable unknown extensions: %s",
extra_extensions);
return strdup(extra_extensions);
}
}
/**
* \brief Free extra_extensions string
*
* These strings are allocated early during the first context creation by
* _mesa_one_time_init_extension_overrides.
*/
static void
free_unknown_extensions_strings(void)
{
free(extra_extensions);
}
/**
* \brief Initialize extension override tables.
*
* This should be called one time early during first context initialization.
*/
void
_mesa_one_time_init_extension_overrides(void)
{
const char *env_const = getenv("MESA_EXTENSION_OVERRIDE");
char *env;
char *ext;
int len;
size_t offset;
atexit(free_unknown_extensions_strings);
memset(&_mesa_extension_override_enables, 0, sizeof(struct gl_extensions));
memset(&_mesa_extension_override_disables, 0, sizeof(struct gl_extensions));
if (env_const == NULL) {
return;
}
/* extra_exts: List of unrecognized extensions. */
extra_extensions = calloc(ALIGN(strlen(env_const) + 2, 4), sizeof(char));
/* Copy env_const because strtok() is destructive. */
env = strdup(env_const);
if (env == NULL ||
extra_extensions == NULL) {
free(env);
free(extra_extensions);
return;
}
for (ext = strtok(env, " "); ext != NULL; ext = strtok(NULL, " ")) {
int enable;
int i;
bool recognized;
switch (ext[0]) {
case '+':
enable = 1;
++ext;
break;
case '-':
enable = 0;
++ext;
break;
default:
enable = 1;
break;
}
i = name_to_index(ext);
offset = set_extension(&_mesa_extension_override_enables, i, enable);
if (offset != 0 && (offset != o(dummy_true) || enable != GL_FALSE)) {
((GLboolean *) &_mesa_extension_override_disables)[offset] = !enable;
recognized = true;
} else {
recognized = false;
}
if (i >= 0)
disabled_extensions[i] = !enable;
if (!recognized && enable) {
strcat(extra_extensions, ext);
strcat(extra_extensions, " ");
}
}
free(env);
/* Remove trailing space, and free if unused. */
len = strlen(extra_extensions);
if (len == 0) {
free(extra_extensions);
extra_extensions = NULL;
} else if (extra_extensions[len - 1] == ' ') {
extra_extensions[len - 1] = '\0';
}
}
/**
* \brief Initialize extension tables and enable default extensions.
*
* This should be called during context initialization.
* Note: Sets gl_extensions.dummy_true to true.
*/
void
_mesa_init_extensions(struct gl_extensions *extensions)
{
GLboolean *base = (GLboolean *) extensions;
GLboolean *sentinel = base + o(extension_sentinel);
GLboolean *i;
/* First, turn all extensions off. */
for (i = base; i != sentinel; ++i)
*i = GL_FALSE;
/* Then, selectively turn default extensions on. */
extensions->dummy_true = GL_TRUE;
}
typedef unsigned short extension_index;
/**
* Given an extension enum, return whether or not the extension is supported
* dependent on the following factors:
* There's driver support and the OpenGL/ES version is at least that
* specified in the _mesa_extension_table.
*/
static inline bool
_mesa_extension_supported(const struct gl_context *ctx, extension_index i)
{
const bool *base = (bool *) &ctx->Extensions;
const struct mesa_extension *ext = _mesa_extension_table + i;
return !disabled_extensions[i] &&
(ctx->Version >= ext->version[ctx->API]) && base[ext->offset];
}
/**
* Compare two entries of the extensions table. Sorts first by year,
* then by name.
*
* Arguments are indices into _mesa_extension_table.
*/
static int
extension_compare(const void *p1, const void *p2)
{
extension_index i1 = * (const extension_index *) p1;
extension_index i2 = * (const extension_index *) p2;
const struct mesa_extension *e1 = &_mesa_extension_table[i1];
const struct mesa_extension *e2 = &_mesa_extension_table[i2];
int res;
res = (int)e1->year - (int)e2->year;
if (res == 0) {
res = strcmp(e1->name, e2->name);
}
return res;
}
/**
* Construct the GL_EXTENSIONS string. Called the first time that
* glGetString(GL_EXTENSIONS) is called.
*/
GLubyte*
_mesa_make_extension_string(struct gl_context *ctx)
{
/* The extension string. */
char *exts = 0;
/* Length of extension string. */
size_t length = 0;
/* Number of extensions */
unsigned count;
/* Indices of the extensions sorted by year */
extension_index *extension_indices;
/* String of extra extensions. */
char *extra_extensions = get_extension_override(ctx);
unsigned k;
unsigned j;
unsigned maxYear = ~0;
/* Check if the MESA_EXTENSION_MAX_YEAR env var is set */
{
const char *env = getenv("MESA_EXTENSION_MAX_YEAR");
if (env) {
maxYear = atoi(env);
_mesa_debug(ctx, "Note: limiting GL extensions to %u or earlier\n",
maxYear);
}
}
/* Compute length of the extension string. */
count = 0;
for (k = 0; k < MESA_EXTENSION_COUNT; ++k) {
const struct mesa_extension *i = _mesa_extension_table + k;
if (i->year <= maxYear &&
_mesa_extension_supported(ctx, k)) {
length += strlen(i->name) + 1; /* +1 for space */
++count;
}
}
if (extra_extensions != NULL)
length += 1 + strlen(extra_extensions); /* +1 for space */
exts = calloc(ALIGN(length + 1, 4), sizeof(char));
if (exts == NULL) {
free(extra_extensions);
return NULL;
}
extension_indices = malloc(count * sizeof(extension_index));
if (extension_indices == NULL) {
free(exts);
free(extra_extensions);
return NULL;
}
/* Sort extensions in chronological order because certain old applications
* (e.g., Quake3 demo) store the extension list in a static size buffer so
* chronologically order ensure that the extensions that such applications
* expect will fit into that buffer.
*/
j = 0;
for (k = 0; k < MESA_EXTENSION_COUNT; ++k) {
if (_mesa_extension_table[k].year <= maxYear &&
_mesa_extension_supported(ctx, k)) {
extension_indices[j++] = k;
}
}
assert(j == count);
qsort(extension_indices, count,
sizeof *extension_indices, extension_compare);
/* Build the extension string.*/
for (j = 0; j < count; ++j) {
const struct mesa_extension *i = &_mesa_extension_table[extension_indices[j]];
assert(_mesa_extension_supported(ctx, extension_indices[j]));
strcat(exts, i->name);
strcat(exts, " ");
}
free(extension_indices);
if (extra_extensions != 0) {
strcat(exts, extra_extensions);
free(extra_extensions);
}
return (GLubyte *) exts;
}
/**
* Return number of enabled extensions.
*/
GLuint
_mesa_get_extension_count(struct gl_context *ctx)
{
unsigned k;
/* only count once */
if (ctx->Extensions.Count != 0)
return ctx->Extensions.Count;
for (k = 0; k < MESA_EXTENSION_COUNT; ++k) {
if (_mesa_extension_supported(ctx, k))
ctx->Extensions.Count++;
}
return ctx->Extensions.Count;
}
/**
* Return name of i-th enabled extension
*/
const GLubyte *
_mesa_get_enabled_extension(struct gl_context *ctx, GLuint index)
{
size_t n = 0;
unsigned i;
for (i = 0; i < MESA_EXTENSION_COUNT; ++i) {
if (_mesa_extension_supported(ctx, i)) {
if (n == index)
return (const GLubyte*) _mesa_extension_table[i].name;
else
++n;
}
}
return NULL;
}