/*
* Copyright (c) 2002-2011 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.BufferUtils;
import org.lwjgl.LWJGLUtil;
import org.lwjgl.MemoryUtil;
import java.nio.*;
/**
* Utility class for OpenGL API calls. Instances of APIUtil are created in ContextCapabilities,
* so we have an instance per OpenGL context.
*
* @author spasi
*/
final class APIUtil {
private static final int INITIAL_BUFFER_SIZE = 256;
private static final int INITIAL_LENGTHS_SIZE = 4;
private static final int BUFFERS_SIZE = 32;
private char[] array;
private ByteBuffer buffer;
private IntBuffer lengths;
private final IntBuffer ints;
private final LongBuffer longs;
private final FloatBuffer floats;
private final DoubleBuffer doubles;
APIUtil() {
array = new char[INITIAL_BUFFER_SIZE];
buffer = BufferUtils.createByteBuffer(INITIAL_BUFFER_SIZE);
lengths = BufferUtils.createIntBuffer(INITIAL_LENGTHS_SIZE);
ints = BufferUtils.createIntBuffer(BUFFERS_SIZE);
longs = BufferUtils.createLongBuffer(BUFFERS_SIZE);
floats = BufferUtils.createFloatBuffer(BUFFERS_SIZE);
doubles = BufferUtils.createDoubleBuffer(BUFFERS_SIZE);
}
private static char[] getArray(final ContextCapabilities caps, final int size) {
char[] array = caps.util.array;
if ( array.length < size ) {
int sizeNew = array.length << 1;
while ( sizeNew < size )
sizeNew <<= 1;
array = new char[size];
caps.util.array = array;
}
return array;
}
static ByteBuffer getBufferByte(final ContextCapabilities caps, final int size) {
ByteBuffer buffer = caps.util.buffer;
if ( buffer.capacity() < size ) {
int sizeNew = buffer.capacity() << 1;
while ( sizeNew < size )
sizeNew <<= 1;
buffer = BufferUtils.createByteBuffer(size);
caps.util.buffer = buffer;
} else
buffer.clear();
return buffer;
}
private static ByteBuffer getBufferByteOffset(final ContextCapabilities caps, final int size) {
ByteBuffer buffer = caps.util.buffer;
if ( buffer.capacity() < size ) {
int sizeNew = buffer.capacity() << 1;
while ( sizeNew < size )
sizeNew <<= 1;
final ByteBuffer bufferNew = BufferUtils.createByteBuffer(size);
bufferNew.put(buffer);
caps.util.buffer = (buffer = bufferNew);
} else {
buffer.position(buffer.limit());
buffer.limit(buffer.capacity());
}
return buffer;
}
static IntBuffer getBufferInt(final ContextCapabilities caps) { return caps.util.ints; }
static LongBuffer getBufferLong(final ContextCapabilities caps) { return caps.util.longs; }
static FloatBuffer getBufferFloat(final ContextCapabilities caps) { return caps.util.floats; }
static DoubleBuffer getBufferDouble(final ContextCapabilities caps) { return caps.util.doubles; }
static IntBuffer getLengths(final ContextCapabilities caps) {
return getLengths(caps, 1);
}
static IntBuffer getLengths(final ContextCapabilities caps, final int size) {
IntBuffer lengths = caps.util.lengths;
if ( lengths.capacity() < size ) {
int sizeNew = lengths.capacity();
while ( sizeNew < size )
sizeNew <<= 1;
lengths = BufferUtils.createIntBuffer(size);
caps.util.lengths = lengths;
} else
lengths.clear();
return lengths;
}
/**
* Simple ASCII encoding.
*
* @param buffer The target buffer
* @param string The source string
*/
private static ByteBuffer encode(final ByteBuffer buffer, final CharSequence string) {
for ( int i = 0; i < string.length(); i++ ) {
final char c = string.charAt(i);
if ( LWJGLUtil.DEBUG && 0x80 <= c ) // Silently ignore and map to 0x1A.
buffer.put((byte)0x1A);
else
buffer.put((byte)c);
}
return buffer;
}
/**
* Reads a byte string from the specified buffer.
*
* @param buffer
*
* @return the buffer as a String.
*/
static String getString(final ContextCapabilities caps, final ByteBuffer buffer) {
final int length = buffer.remaining();
final char[] charArray = getArray(caps, length);
for ( int i = buffer.position(); i < buffer.limit(); i++ )
charArray[i - buffer.position()] = (char)buffer.get(i);
return new String(charArray, 0, length);
}
/**
* Returns a buffer containing the specified string as bytes.
*
* @param string
*
* @return the String as a ByteBuffer
*/
static long getBuffer(final ContextCapabilities caps, final CharSequence string) {
final ByteBuffer buffer = encode(getBufferByte(caps, string.length()), string);
buffer.flip();
return MemoryUtil.getAddress0(buffer);
}
/**
* Returns a buffer containing the specified string as bytes, starting at the specified offset.
*
* @param string
*
* @return the String as a ByteBuffer
*/
static long getBuffer(final ContextCapabilities caps, final CharSequence string, final int offset) {
final ByteBuffer buffer = encode(getBufferByteOffset(caps, offset + string.length()), string);
buffer.flip();
return MemoryUtil.getAddress(buffer);
}
/**
* Returns a buffer containing the specified string as bytes, including null-termination.
*
* @param string
*
* @return the String as a ByteBuffer
*/
static long getBufferNT(final ContextCapabilities caps, final CharSequence string) {
final ByteBuffer buffer = encode(getBufferByte(caps, string.length() + 1), string);
buffer.put((byte)0);
buffer.flip();
return MemoryUtil.getAddress0(buffer);
}
static int getTotalLength(final CharSequence[] strings) {
int length = 0;
for ( CharSequence string : strings )
length += string.length();
return length;
}
/**
* Returns a buffer containing the specified strings as bytes.
*
* @param strings
*
* @return the Strings as a ByteBuffer
*/
static long getBuffer(final ContextCapabilities caps, final CharSequence[] strings) {
final ByteBuffer buffer = getBufferByte(caps, getTotalLength(strings));
for ( CharSequence string : strings )
encode(buffer, string);
buffer.flip();
return MemoryUtil.getAddress0(buffer);
}
/**
* Returns a buffer containing the specified strings as bytes, including null-termination.
*
* @param strings
*
* @return the Strings as a ByteBuffer
*/
static long getBufferNT(final ContextCapabilities caps, final CharSequence[] strings) {
final ByteBuffer buffer = getBufferByte(caps, getTotalLength(strings) + strings.length);
for ( CharSequence string : strings ) {
encode(buffer, string);
buffer.put((byte)0);
}
buffer.flip();
return MemoryUtil.getAddress0(buffer);
}
/**
* Returns a buffer containing the lengths of the specified strings.
*
* @param strings
*
* @return the String lengths in an IntBuffer
*/
static long getLengths(final ContextCapabilities caps, final CharSequence[] strings) {
IntBuffer buffer = getLengths(caps, strings.length);
for ( CharSequence string : strings )
buffer.put(string.length());
buffer.flip();
return MemoryUtil.getAddress0(buffer);
}
static long getInt(final ContextCapabilities caps, final int value) {
return MemoryUtil.getAddress0(getBufferInt(caps).put(0, value));
}
static long getBufferByte0(final ContextCapabilities caps) {
return MemoryUtil.getAddress0(getBufferByte(caps, 0));
}
}