/*
* Copyright (c) 2002-2004 LWJGL Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* * Neither the name of 'LWJGL' nor the names of
* its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.lwjgl.opengl;
import org.lwjgl.LWJGLException;
import org.lwjgl.Sys;
import java.lang.ref.WeakReference;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.*;
/**
* $Id$
*
* @version $Revision$
*/
public final class GLContext {
/**
* The currently initialised context
*/
private static WeakReference currentContext;
/*
* Available extensions
*/
public static boolean GL_ARB_depth_texture;
public static boolean GL_ARB_draw_buffers;
public static boolean GL_ARB_fragment_program;
public static boolean GL_ARB_fragment_program_shadow;
public static boolean GL_ARB_fragment_shader;
public static boolean GL_ARB_imaging;
public static boolean GL_ARB_matrix_palette;
public static boolean GL_ARB_multisample;
public static boolean GL_ARB_multitexture;
public static boolean GL_ARB_occlusion_query;
public static boolean GL_ARB_point_parameters;
public static boolean GL_ARB_point_sprite;
public static boolean GL_ARB_shading_language_100;
public static boolean GL_ARB_shader_objects;
public static boolean GL_ARB_shadow;
public static boolean GL_ARB_shadow_ambient;
public static boolean GL_ARB_texture_border_clamp;
public static boolean GL_ARB_texture_compression;
public static boolean GL_ARB_texture_cube_map;
public static boolean GL_ARB_texture_env_add;
public static boolean GL_ARB_texture_env_combine;
public static boolean GL_ARB_texture_env_crossbar;
public static boolean GL_ARB_texture_env_dot3;
public static boolean GL_ARB_texture_mirrored_repeat;
public static boolean GL_ARB_texture_non_power_of_two;
public static boolean GL_ARB_texture_rectangle;
public static boolean GL_ARB_transpose_matrix;
public static boolean GL_ARB_vertex_blend;
public static boolean GL_ARB_vertex_buffer_object;
public static boolean GL_ARB_vertex_program;
public static boolean GL_ARB_vertex_shader;
public static boolean GL_ARB_window_pos;
public static boolean GL_EXT_abgr;
public static boolean GL_EXT_bgra;
public static boolean GL_EXT_blend_equation_separate;
public static boolean GL_EXT_blend_func_separate;
public static boolean GL_EXT_blend_subtract;
public static boolean GL_EXT_Cg_shader;
public static boolean GL_EXT_compiled_vertex_array;
public static boolean GL_EXT_depth_bounds_test;
public static boolean GL_EXT_draw_range_elements;
public static boolean GL_EXT_fog_coord;
public static boolean GL_EXT_multi_draw_arrays;
public static boolean GL_EXT_packed_pixels;
public static boolean GL_EXT_pixel_buffer_object;
public static boolean GL_EXT_point_parameters;
public static boolean GL_EXT_rescale_normal;
public static boolean GL_EXT_secondary_color;
public static boolean GL_EXT_separate_specular_color;
public static boolean GL_EXT_shadow_funcs;
public static boolean GL_EXT_shared_texture_palette;
public static boolean GL_EXT_stencil_two_side;
public static boolean GL_EXT_stencil_wrap;
public static boolean GL_EXT_texture_compression_s3tc;
public static boolean GL_EXT_texture_env_combine;
public static boolean GL_EXT_texture_env_dot3;
public static boolean GL_EXT_texture_filter_anisotropic;
public static boolean GL_EXT_texture_lod_bias;
public static boolean GL_EXT_texture_mirror_clamp;
public static boolean GL_EXT_texture_rectangle;
public static boolean GL_EXT_vertex_shader;
public static boolean GL_EXT_vertex_weighting;
public static boolean GL_ATI_draw_buffers;
public static boolean GL_ATI_element_array;
public static boolean GL_ATI_envmap_bumpmap;
public static boolean GL_ATI_fragment_shader;
public static boolean GL_ATI_map_object_buffer;
public static boolean GL_ATI_pn_triangles;
public static boolean GL_ATI_separate_stencil;
public static boolean GL_ATI_texture_float;
public static boolean GL_ATI_texture_mirror_once;
public static boolean GL_ATI_vertex_array_object;
public static boolean GL_ATI_vertex_streams;
public static boolean GL_ATI_vertex_attrib_array_object;
public static boolean GL_NV_blend_square;
public static boolean GL_NV_copy_depth_to_color;
public static boolean GL_NV_depth_clamp;
public static boolean GL_NV_evaluators;
public static boolean GL_NV_fence;
public static boolean GL_NV_float_buffer;
public static boolean GL_NV_fog_distance;
public static boolean GL_NV_fragment_program;
public static boolean GL_NV_fragment_program2;
public static boolean GL_NV_fragment_program_option;
public static boolean GL_NV_half_float;
public static boolean GL_NV_light_max_exponent;
public static boolean GL_NV_multisample_filter_hint;
public static boolean GL_NV_occlusion_query;
public static boolean GL_NV_packed_depth_stencil;
public static boolean GL_NV_pixel_data_range;
public static boolean GL_NV_point_sprite;
public static boolean GL_NV_primitive_restart;
public static boolean GL_NV_register_combiners;
public static boolean GL_NV_register_combiners2;
public static boolean GL_NV_texgen_reflection;
public static boolean GL_NV_texture_compression_vtc;
public static boolean GL_NV_texture_env_combine4;
public static boolean GL_NV_texture_expand_normal;
public static boolean GL_NV_texture_rectangle;
public static boolean GL_NV_texture_shader;
public static boolean GL_NV_texture_shader2;
public static boolean GL_NV_texture_shader3;
public static boolean GL_NV_vertex_array_range;
public static boolean GL_NV_vertex_array_range2;
public static boolean GL_NV_vertex_program;
public static boolean GL_NV_vertex_program1_1;
public static boolean GL_NV_vertex_program2;
public static boolean GL_NV_vertex_program2_option;
public static boolean GL_NV_vertex_program3;
public static boolean OpenGL11;
public static boolean OpenGL12;
public static boolean OpenGL13;
public static boolean OpenGL14;
public static boolean OpenGL15;
public static boolean OpenGL20;
/**
* Map of classes that have native stubs loaded
*/
private static Map exts;
private static int gl_ref_count;
private static boolean did_auto_load;
private static boolean loaded_stubs;
static {
Sys.initialize();
}
/**
* Determine which extensions are available. Use this to initialize capability fields. Can only be called _after_ the Display
* context or a Pbuffer has been created (or a context from some other GL library). Using LWJGL, this method is called
* automatically for you when the LWJGL Window is created and there is no need to call it yourself.
*
* @param exts A Set of OpenGL extension string names
*/
private static void determineAvailableExtensions(Set exts) {
// Grab all the public static booleans out of this class
Field[] fields = GLContext.class.getDeclaredFields();
for ( int i = 0; i < fields.length; i++ ) {
if ( Modifier.isStatic(fields[i].getModifiers()) && fields[i].getType().equals(boolean.class) ) {
// reset fields
try {
fields[i].setBoolean(GLContext.class, exts.contains(fields[i].getName()));
} catch (IllegalAccessException e) {
e.printStackTrace(System.err);
}
}
}
}
/**
* Makes a GL context the current LWJGL context by loading GL function pointers. The context must be current before a call to
* this method! Instead it simply ensures that the current context is reflected accurately by GLContext's extension caps and
* function pointers. Use useContext(null) when no context is active. If the context is the same as last time, then this is
* a no-op.
If the context has not been encountered before it will be fully initialized from scratch. Otherwise a cached set
* of caps and function pointers will be used.
The reference to the context is held in a weak reference; therefore if no
* strong reference exists to the GL context it will automatically be forgotten by the VM at an indeterminate point in the
* future, freeing up a little RAM.
*
* @param context The context object, which uniquely identifies a GL context. If context is null, the native stubs are
* unloaded.
*
* @throws LWJGLException if context non-null, and the gl library can't be loaded or the basic GL11 functions can't be loaded
*/
public static void useContext(Object context) throws LWJGLException {
if ( context == null ) {
unloadStubs();
if ( did_auto_load )
unloadOpenGLLibrary();
currentContext = null;
VBOTracker.setCurrent(null);
return;
}
// Is this the same as last time?
Object current = currentContext == null ? null : currentContext.get();
if ( current == context ) {
// Yes, so we don't need to do anything. Our caps and function pointers are still valid.
return;
}
// Ok, now it's the current context.
if ( gl_ref_count == 0 ) {
loadOpenGLLibrary();
did_auto_load = true;
}
try {
loadStubs();
currentContext = new WeakReference(context);
VBOTracker.setCurrent(context);
} catch (LWJGLException e) {
if ( did_auto_load )
unloadOpenGLLibrary();
throw e;
}
}
private static void getExtensionClassesAndNames(Map exts, Set exts_names) {
/*
The version number is either of the form
.
or
..
where the numbers all have one or more digits.
*/
String version = GL11.glGetString(GL11.GL_VERSION);
int majorEnd = version.indexOf('.');
int minorEnd = version.indexOf('.', majorEnd + 1);
int majorVersion = Integer.parseInt(version.substring(0, majorEnd));
int minorVersion = Integer.parseInt(version.substring(majorEnd + 1, minorEnd));
if ( majorVersion == 2 ) {
// ----------------------[ 2.X ]----------------------
addExtensionClass(exts, exts_names, "GL20", "OpenGL20");
// ----------------------[ 1.X ]----------------------
addExtensionClass(exts, exts_names, "GL15", "OpenGL15");
addExtensionClass(exts, exts_names, "GL14", "OpenGL14");
addExtensionClass(exts, exts_names, "GL13", "OpenGL13");
addExtensionClass(exts, exts_names, "GL12", "OpenGL12");
} else {
switch ( minorVersion ) {
case 5:
addExtensionClass(exts, exts_names, "GL15", "OpenGL15");
case 4:
addExtensionClass(exts, exts_names, "GL14", "OpenGL14");
case 3:
addExtensionClass(exts, exts_names, "GL13", "OpenGL13");
case 2:
addExtensionClass(exts, exts_names, "GL12", "OpenGL12");
}
}
addExtensionClass(exts, exts_names, "EXTTextureCompressionS3TC", "");
String extensions_string = GL11.glGetString(GL11.GL_EXTENSIONS);
StringTokenizer tokenizer = new StringTokenizer(extensions_string);
while ( tokenizer.hasMoreTokens() ) {
String extension_string = tokenizer.nextToken();
StringBuffer converted_name = new StringBuffer();
int gl_prefix_index = extension_string.indexOf("GL_");
if ( gl_prefix_index == -1 )
continue;
if ( "GL_EXT_texture_compression_s3tc".equals(extension_string) ) {
// Special workaround
addExtensionClass(exts, exts_names, "EXTTextureCompressionS3TC", "GL_EXT_texture_compression_s3tc");
} else if ( "GL_EXT_texture_lod_bias".equals(extension_string) ) {
// Special workaround
addExtensionClass(exts, exts_names, "EXTTextureLODBias", "GL_EXT_texture_lod_bias");
} else if ( "GL_NV_texture_compression_vtc".equals(extension_string) ) {
// Special workaround
addExtensionClass(exts, exts_names, "NVTextureCompressionVTC", "GL_NV_texture_compression_vtc");
} else {
for ( int i = gl_prefix_index + 3; i < extension_string.length(); i++ ) {
char c;
if ( extension_string.charAt(i) == '_' ) {
i++;
c = Character.toUpperCase(extension_string.charAt(i));
} else
c = extension_string.charAt(i);
converted_name.append(c);
}
addExtensionClass(exts, exts_names, converted_name.toString(), extension_string);
}
}
addExtensionClass(exts, exts_names, "ARBBufferObject", null);
addExtensionClass(exts, exts_names, "ARBProgram", null);
addExtensionClass(exts, exts_names, "NVProgram", null);
}
private static void addExtensionClass(Map exts, Set exts_names, String ext_class_name, String ext_name) {
if ( ext_name != null ) {
if ( exts_names.contains(ext_name) ) {
// Already added; ignore
return;
}
exts_names.add(ext_name);
}
try {
Class extension_class = Class.forName("org.lwjgl.opengl." + ext_class_name);
extension_class.getDeclaredMethod("initNativeStubs", null); // check for existance of initNativeStubs method
exts.put(extension_class, ext_name);
} catch (ClassNotFoundException e) {
// ignore
} catch (NoSuchMethodException e) {
// ignore
}
}
private static void loadStubs() throws LWJGLException {
if ( loaded_stubs )
return;
GL11.initNativeStubs();
exts = new HashMap();
Set exts_names = new HashSet();
getExtensionClassesAndNames(exts, exts_names);
Iterator exts_it = exts.keySet().iterator();
while ( exts_it.hasNext() ) {
Class extension_class = (Class)exts_it.next();
resetNativeStubs(extension_class);
try {
Method init_stubs_method = extension_class.getDeclaredMethod("initNativeStubs", null);
init_stubs_method.invoke(null, null);
} catch (Exception e) {
Sys.log("Failed to initialize extension " + extension_class);
exts_it.remove();
exts_names.remove(exts.get(extension_class));
}
}
determineAvailableExtensions(exts_names);
loaded_stubs = true;
}
private static void unloadStubs() {
if ( !loaded_stubs )
return;
loaded_stubs = false;
Iterator exts_it = exts.keySet().iterator();
while ( exts_it.hasNext() ) {
Class ext_class = (Class)exts_it.next();
resetNativeStubs(ext_class);
}
resetNativeStubs(org.lwjgl.opengl.GL11.class);
}
/**
* If the OpenGL reference count is 0, the library is loaded. The reference count is then incremented.
*/
public static void loadOpenGLLibrary() throws LWJGLException {
if ( gl_ref_count == 0 )
nLoadOpenGLLibrary();
gl_ref_count++;
}
private static native void nLoadOpenGLLibrary() throws LWJGLException;
/**
* The OpenGL library reference count is decremented, and if it reaches 0, the library is unloaded.
*/
public static void unloadOpenGLLibrary() {
gl_ref_count--;
if ( gl_ref_count == 0 )
nUnloadOpenGLLibrary();
}
private static native void nUnloadOpenGLLibrary();
/**
* Native method to clear native stub bindings
*/
private static native void resetNativeStubs(Class clazz);
}