path: root/Minecraft.World/ByteBuffer.cpp

#include "stdafx.h"

#include "IntBuffer.h"
#include "FloatBuffer.h"
#include "ByteBuffer.h"

ByteBuffer::ByteBuffer( unsigned int capacity ) : Buffer( capacity )
{
	hasBackingArray = false;
	buffer = new byte[capacity];
	memset( buffer,0,sizeof(byte)*capacity);
	byteOrder = BIGENDIAN;
}

//Allocates a new direct byte buffer.
//The new buffer's position will be zero, its limit will be its capacity, and its mark will be undefined. Whether or not it has a backing array is unspecified.
//
//Parameters:
//capacity - The new buffer's capacity, in bytes
//Returns:
//The new byte buffer
ByteBuffer *ByteBuffer::allocateDirect(int capacity)
{
	return new ByteBuffer(capacity);
}


ByteBuffer::ByteBuffer( unsigned int capacity, byte *backingArray ) : Buffer( capacity )
{
	hasBackingArray = true;
	buffer = backingArray;
}

ByteBuffer::~ByteBuffer()
{
	if( !hasBackingArray )
		delete[] buffer;
}

//Wraps a byte array into a buffer.
//The new buffer will be backed by the given byte array; that is, modifications to the buffer will cause the array
//to be modified and vice versa. The new buffer's capacity and limit will be array.length, its position will be zero,
//and its mark will be undefined. Its backing array will be the given array, and its array offset will be zero.
//
//Parameters:
//array - The array that will back this buffer
//Returns:
//The new byte buffer
ByteBuffer *ByteBuffer::wrap(byteArray &b)
{
	return new ByteBuffer( b.length, b.data );
}

//Allocates a new byte buffer.
//The new buffer's position will be zero, its limit will be its capacity, and its mark will be undefined.
//It will have a backing array, and its array offset will be zero.
//
//Parameters:
//capacity - The new buffer's capacity, in bytes
//Returns:
//The new byte buffer
ByteBuffer *ByteBuffer::allocate(unsigned int capacity)
{
	return new ByteBuffer( capacity );
}

//Modifies this buffer's byte order.
//Parameters:
//bo - The new byte order, either BIGENDIAN or LITTLEENDIAN
void ByteBuffer::order(ByteOrder bo)
{
	byteOrder = bo;
}

//Flips this buffer. The limit is set to the current position and then the position is set to zero.
//If the mark is defined then it is discarded.
//
//Returns:
//This buffer
ByteBuffer *ByteBuffer::flip()
{
	m_limit = m_position;
	m_position = 0;
	return this;
}

// 4J Added so we can write this to a file
byte *ByteBuffer::getBuffer()
{
	return buffer;
}

int ByteBuffer::getSize()
{
	// TODO 4J Stu - Should this be the capcity and not the limit?
	return m_limit;
}
// End 4J

//Absolute get method. Reads the byte at the given index.
//Parameters:
//index - The index from which the byte will be read
//Returns:
//The byte at the given index
//Throws:
//IndexOutOfBoundsException - If index is negative or not smaller than the buffer's limit
BYTE ByteBuffer::get(int index)
{
	assert( index < m_limit );
	assert( index >= 0 );

	return buffer[index];
}

//Relative get method for reading an int value.
//Reads the next four bytes at this buffer's current position, composing them into an int value according to the
//current byte order, and then increments the position by four.
//
//Returns:
//The int value at the buffer's current position
int ByteBuffer::getInt()
{
	assert( m_position+3 < m_limit );

	int value = 0;

	int b1 = buffer[ m_position ];
	int b2 = buffer[ m_position+1 ];
	int b3 = buffer[ m_position+2 ];
	int b4 = buffer[ m_position+3 ];

	m_position += 4;

	if( byteOrder == BIGENDIAN )
	{
		value = (b1 << 24) | (b2 << 16) | (b3 << 8) | b4;
	}
	else if( byteOrder == LITTLEENDIAN )
	{
		value = b1 | (b2 << 8) | (b3 << 16) | (b4 << 24);
	}
	return value;
}

//Absolute get method for reading an int value.
//Reads four bytes at the given index, composing them into a int value according to the current byte order.
//
//Parameters:
//index - The index from which the bytes will be read
//Returns:
//The int value at the given index
int ByteBuffer::getInt(unsigned int index)
{
	assert( index+3 < m_limit );
	int value = 0;

	int b1 = buffer[ index ];
	int b2 = buffer[ index+1 ];
	int b3 = buffer[ index+2 ];
	int b4 = buffer[ index+3 ];

	if( byteOrder == BIGENDIAN )
	{
		value = (b1 << 24) | (b2 << 16) | (b3 << 8) | b4;
	}
	else if( byteOrder == LITTLEENDIAN )
	{
		value = b1 | (b2 << 8) | (b3 << 16) | (b4 << 24);
	}
	return value;
}

//Relative get method for reading a long value.
//Reads the next eight bytes at this buffer's current position, composing them into a long value according to the current byte order,
//and then increments the position by eight.
//
//Returns:
//The long value at the buffer's current position
int64_t ByteBuffer::getLong()
{
	assert( m_position+8 < m_limit );

	int64_t value = 0;

	int64_t b1 = buffer[ m_position ];
	int64_t b2 = buffer[ m_position+1 ];
	int64_t b3 = buffer[ m_position+2 ];
	int64_t b4 = buffer[ m_position+3 ];
	int64_t b5 = buffer[ m_position+4 ];
	int64_t b6 = buffer[ m_position+5 ];
	int64_t b7 = buffer[ m_position+6 ];
	int64_t b8 = buffer[ m_position+7 ];

	m_position += 8;

	if( byteOrder == BIGENDIAN )
	{
		value = (b1 << 56) | (b2 << 48) | (b3 << 40) | (b4 << 32) | (b5 << 24) | (b6 << 16) | (b7 << 8) | b8;
	}
	else if( byteOrder == LITTLEENDIAN )
	{
		value = b1 | (b2 << 8) | (b3 << 16) | (b4 << 24) | (b5 << 32) | (b6 << 40) | (b7 << 48) | (b8 << 56);
	}
	return value;
}

//Relative get method for reading a short value.
//Reads the next two bytes at this buffer's current position, composing them into a short value according to the current
//byte order, and then increments the position by two.
//
//Returns:
//The short value at the buffer's current position
short ByteBuffer::getShort()
{
	assert( m_position+1 < m_limit );

	short value = 0;

	short b1 = buffer[ m_position ];
	short b2 = buffer[ m_position+1 ];

	m_position += 2;

	if( byteOrder == BIGENDIAN )
	{
		value = (b1 << 8) | b2;
	}
	else if( byteOrder == LITTLEENDIAN )
	{
		value = b1 | (b2 << 8);
	}
	return value;
}

void ByteBuffer::getShortArray(shortArray &s)
{
	// TODO 4J Stu - Should this function be writing from the start of the buffer, or from position?
	// And should it update position?
	assert( s.length >= m_limit/2 );

	// 4J Stu - Assumes big endian
	memcpy( s.data, buffer, (m_limit-m_position) );
}

//Absolute put method  (optional operation).
//Writes the given byte into this buffer at the given index.
//
//Parameters:
//index - The index at which the byte will be written
//b - The byte value to be written
//Returns:
//This buffer
//Throws:
//IndexOutOfBoundsException - If index is negative or not smaller than the buffer's limit
//ReadOnlyBufferException - If this buffer is read-only
ByteBuffer *ByteBuffer::put(int index, byte b)
{
	assert( index < m_limit );
	assert( index >= 0 );

	buffer[index] = b;
	return this;
}


//Relative put method for writing an int value  (optional operation).
//Writes four bytes containing the given int value, in the current byte order, into this buffer at the current position,
//and then increments the position by four.
//
//Parameters:
//value - The int value to be written
//Returns:
//This buffer
ByteBuffer *ByteBuffer::putInt(int value)
{
	assert( m_position+3 < m_limit );

	if( byteOrder == BIGENDIAN )
	{
		buffer[m_position] = (value >> 24) & 0xFF;
		buffer[m_position+1] = (value >> 16) & 0xFF;
		buffer[m_position+2] = (value >> 8) & 0xFF;
		buffer[m_position+3] = value & 0xFF;
	}
	else if( byteOrder == LITTLEENDIAN )
	{
		buffer[m_position] = value & 0xFF;
		buffer[m_position+1] = (value >> 8) & 0xFF;
		buffer[m_position+2] = (value >> 16) & 0xFF;
		buffer[m_position+3] = (value >> 24) & 0xFF;
	}

	m_position += 4;

	return this;
}

//Absolute put method for writing an int value  (optional operation).
//Writes four bytes containing the given int value, in the current byte order, into this buffer at the given index.
//
//Parameters:
//index - The index at which the bytes will be written
//value - The int value to be written
//Returns:
//This buffer
ByteBuffer *ByteBuffer::putInt(unsigned int index, int value)
{
	assert( index+3 < m_limit );

	if( byteOrder == BIGENDIAN )
	{
		buffer[index] = (value >> 24) & 0xFF;
		buffer[index+1] = (value >> 16) & 0xFF;
		buffer[index+2] = (value >> 8) & 0xFF;
		buffer[index+3] = value & 0xFF;
	}
	else if( byteOrder == LITTLEENDIAN )
	{
		buffer[index] = value & 0xFF;
		buffer[index+1] = (value >> 8) & 0xFF;
		buffer[index+2] = (value >> 16) & 0xFF;
		buffer[index+3] = (value >> 24) & 0xFF;
	}

	return this;
}

//Relative put method for writing a short value  (optional operation).
//Writes two bytes containing the given short value, in the current byte order, into this buffer at the current position,
//and then increments the position by two.
//
//Parameters:
//value - The short value to be written
//Returns:
//This buffer
ByteBuffer *ByteBuffer::putShort(short value)
{
	assert( m_position+1 < m_limit );

	if( byteOrder == BIGENDIAN )
	{
		buffer[m_position] = (value >> 8) & 0xFF;
		buffer[m_position+1] = value & 0xFF;
	}
	else if( byteOrder == LITTLEENDIAN )
	{
		buffer[m_position] = value & 0xFF;
		buffer[m_position+1] = (value >> 8) & 0xFF;
	}

	m_position += 2;

	return this;
}

ByteBuffer *ByteBuffer::putShortArray(shortArray &s)
{
	// TODO 4J Stu - Should this function be writing from the start of the buffer, or from position?
	// And should it update position?
	assert( s.length*2 <= m_limit);

	// 4J Stu - Assumes big endian
	memcpy( buffer, s.data, s.length*2 );

	return this;
}

//Relative put method for writing a long value  (optional operation).
//Writes eight bytes containing the given long value, in the current byte order, into this buffer at the current position,
//and then increments the position by eight.
//
//Parameters:
//value - The long value to be written
//Returns:
//This buffer
ByteBuffer *ByteBuffer::putLong(int64_t value)
{
	assert( m_position+7 < m_limit );

	if( byteOrder == BIGENDIAN )
	{
		buffer[m_position] = (value >> 56) & 0xFF;
		buffer[m_position+1] = (value >> 48) & 0xFF;
		buffer[m_position+2] = (value >> 40) & 0xFF;
		buffer[m_position+3] = (value >> 32) & 0xFF;
		buffer[m_position+4] = (value >> 24) & 0xFF;
		buffer[m_position+5] = (value >> 16) & 0xFF;
		buffer[m_position+6] = (value >> 8) & 0xFF;
		buffer[m_position+7] = value & 0xFF;
	}
	else if( byteOrder == LITTLEENDIAN )
	{
		buffer[m_position] = value & 0xFF;
		buffer[m_position+1] = (value >> 8) & 0xFF;
		buffer[m_position+2] = (value >> 16) & 0xFF;
		buffer[m_position+3] = (value >> 24) & 0xFF;
		buffer[m_position+4] = (value >> 32) & 0xFF;
		buffer[m_position+5] = (value >> 40) & 0xFF;
		buffer[m_position+6] = (value >> 48) & 0xFF;
		buffer[m_position+7] = (value >> 56) & 0xFF;
	}

	return this;
}

//Relative bulk put method  (optional operation).
//This method transfers the entire content of the given source byte array into this buffer.
//An invocation of this method of the form dst.put(a) behaves in exactly the same way as the invocation
//
//     dst.put(a, 0, a.length)
//Returns:
//This buffer
ByteBuffer *ByteBuffer::put(byteArray inputArray)
{
	if( inputArray.length > remaining() )
		assert( false ); //TODO 4J Stu - Some kind of exception?

	std::copy( inputArray.data, inputArray.data + inputArray.length, buffer+m_position );

	m_position += inputArray.length;

	return this;
}

byteArray ByteBuffer::array()
{
	return byteArray( buffer, m_capacity );
}

//Creates a view of this byte buffer as an int buffer.
//The content of the new buffer will start at this buffer's current position. Changes to this buffer's content
//will be visible in the new buffer, and vice versa; the two buffers' position, limit, and mark values will be independent.
//
//The new buffer's position will be zero, its capacity and its limit will be the number of bytes remaining in this buffer
//divided by four, and its mark will be undefined. The new buffer will be direct if, and only if, this buffer is direct, and
//it will be read-only if, and only if, this buffer is read-only.
//
//Returns:
//A new int buffer
IntBuffer *ByteBuffer::asIntBuffer()
{
	// TODO 4J Stu - Is it safe to just cast our byte array pointer to another type?
	return new IntBuffer( (m_limit-m_position)/4, (int *) (buffer+m_position) );
}

//Creates a view of this byte buffer as a float buffer.
//The content of the new buffer will start at this buffer's current position. Changes to this buffer's content will be
//visible in the new buffer, and vice versa; the two buffers' position, limit, and mark values will be independent.
//
//The new buffer's position will be zero, its capacity and its limit will be the number of bytes remaining in this buffer
//divided by four, and its mark will be undefined. The new buffer will be direct if, and only if, this buffer is direct,
//and it will be read-only if, and only if, this buffer is read-only.
//
//Returns:
//A new float buffer
FloatBuffer *ByteBuffer::asFloatBuffer()
{
	// TODO 4J Stu - Is it safe to just cast our byte array pointer to another type?
	return new FloatBuffer( (m_limit-m_position)/4, (float *) (buffer+m_position) );
}



#ifdef __PS3__
// we're using the RSX now to upload textures to vram, so we need th main ram textures allocated from io space
ByteBuffer_IO::ByteBuffer_IO( unsigned int capacity )
	: ByteBuffer(capacity, (byte*)RenderManager.allocIOMem(capacity, 64))
{
	memset( buffer,0,sizeof(byte)*capacity);
	byteOrder = BIGENDIAN;
}

ByteBuffer_IO::~ByteBuffer_IO()
{
//	delete buffer;
	RenderManager.freeIOMem(buffer);
}
#endif // __PS3__