/*******************************************************************************
* Copyright 2011 See AUTHORS file.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
******************************************************************************/
package com.badlogic.gdx.graphics.glutils;
import java.nio.Buffer;
import java.nio.ByteBuffer;
import java.nio.FloatBuffer;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.graphics.GL20;
import com.badlogic.gdx.graphics.VertexAttribute;
import com.badlogic.gdx.graphics.VertexAttributes;
import com.badlogic.gdx.utils.BufferUtils;
import com.badlogic.gdx.utils.GdxRuntimeException;
/** <p>
* A {@link VertexData} implementation based on OpenGL vertex buffer objects.
* <p>
* If the OpenGL ES context was lost you can call {@link #invalidate()} to recreate a new OpenGL vertex buffer object.
* <p>
* The data is bound via glVertexAttribPointer() according to the attribute aliases specified via {@link VertexAttributes}
* in the constructor.
* <p>
* VertexBufferObjects must be disposed via the {@link #dispose()} method when no longer needed
*
* @author mzechner, Dave Clayton <contact@redskyforge.com> */
public class VertexBufferObject implements VertexData {
private VertexAttributes attributes;
private FloatBuffer buffer;
private ByteBuffer byteBuffer;
private boolean ownsBuffer;
private int bufferHandle;
private int usage;
boolean isDirty = false;
boolean isBound = false;
/** Constructs a new interleaved VertexBufferObject.
*
* @param isStatic whether the vertex data is static.
* @param numVertices the maximum number of vertices
* @param attributes the {@link VertexAttribute}s. */
public VertexBufferObject (boolean isStatic, int numVertices, VertexAttribute... attributes) {
this(isStatic, numVertices, new VertexAttributes(attributes));
}
/** Constructs a new interleaved VertexBufferObject.
*
* @param isStatic whether the vertex data is static.
* @param numVertices the maximum number of vertices
* @param attributes the {@link VertexAttributes}. */
public VertexBufferObject (boolean isStatic, int numVertices, VertexAttributes attributes) {
bufferHandle = Gdx.gl20.glGenBuffer();
ByteBuffer data = BufferUtils.newUnsafeByteBuffer(attributes.vertexSize * numVertices);
data.limit(0);
setBuffer(data, true, attributes);
setUsage(isStatic ? GL20.GL_STATIC_DRAW : GL20.GL_DYNAMIC_DRAW);
}
protected VertexBufferObject (int usage, ByteBuffer data, boolean ownsBuffer, VertexAttributes attributes) {
bufferHandle = Gdx.gl20.glGenBuffer();
setBuffer(data, ownsBuffer, attributes);
setUsage(usage);
}
@Override
public VertexAttributes getAttributes () {
return attributes;
}
@Override
public int getNumVertices () {
return buffer.limit() * 4 / attributes.vertexSize;
}
@Override
public int getNumMaxVertices () {
return byteBuffer.capacity() / attributes.vertexSize;
}
@Override
public FloatBuffer getBuffer () {
isDirty = true;
return buffer;
}
/** Low level method to reset the buffer and attributes to the specified values. Use with care!
* @param data
* @param ownsBuffer
* @param value */
protected void setBuffer (Buffer data, boolean ownsBuffer, VertexAttributes value) {
if (isBound) throw new GdxRuntimeException("Cannot change attributes while VBO is bound");
if (this.ownsBuffer && byteBuffer != null)
BufferUtils.disposeUnsafeByteBuffer(byteBuffer);
attributes = value;
if (data instanceof ByteBuffer)
byteBuffer = (ByteBuffer)data;
else
throw new GdxRuntimeException("Only ByteBuffer is currently supported");
this.ownsBuffer = ownsBuffer;
final int l = byteBuffer.limit();
byteBuffer.limit(byteBuffer.capacity());
buffer = byteBuffer.asFloatBuffer();
byteBuffer.limit(l);
buffer.limit(l / 4);
}
private void bufferChanged () {
if (isBound) {
Gdx.gl20.glBufferData(GL20.GL_ARRAY_BUFFER, byteBuffer.limit(), byteBuffer, usage);
isDirty = false;
}
}
@Override
public void setVertices (float[] vertices, int offset, int count) {
isDirty = true;
BufferUtils.copy(vertices, byteBuffer, count, offset);
buffer.position(0);
buffer.limit(count);
bufferChanged();
}
@Override
public void updateVertices (int targetOffset, float[] vertices, int sourceOffset, int count) {
isDirty = true;
final int pos = byteBuffer.position();
byteBuffer.position(targetOffset * 4);
BufferUtils.copy(vertices, sourceOffset, count, byteBuffer);
byteBuffer.position(pos);
buffer.position(0);
bufferChanged();
}
/** @return The GL enum used in the call to {@link GL20#glBufferData(int, int, java.nio.Buffer, int)}, e.g. GL_STATIC_DRAW or
* GL_DYNAMIC_DRAW */
protected int getUsage () {
return usage;
}
/** Set the GL enum used in the call to {@link GL20#glBufferData(int, int, java.nio.Buffer, int)}, can only be called when the
* VBO is not bound. */
protected void setUsage (int value) {
if (isBound) throw new GdxRuntimeException("Cannot change usage while VBO is bound");
usage = value;
}
/** Binds this VertexBufferObject for rendering via glDrawArrays or glDrawElements
* @param shader the shader */
@Override
public void bind (ShaderProgram shader) {
bind(shader, null);
}
@Override
public void bind (ShaderProgram shader, int[] locations) {
final GL20 gl = Gdx.gl20;
gl.glBindBuffer(GL20.GL_ARRAY_BUFFER, bufferHandle);
if (isDirty) {
byteBuffer.limit(buffer.limit() * 4);
gl.glBufferData(GL20.GL_ARRAY_BUFFER, byteBuffer.limit(), byteBuffer, usage);
isDirty = false;
}
final int numAttributes = attributes.size();
if (locations == null) {
for (int i = 0; i < numAttributes; i++) {
final VertexAttribute attribute = attributes.get(i);
final int location = shader.getAttributeLocation(attribute.alias);
if (location < 0) continue;
shader.enableVertexAttribute(location);
shader.setVertexAttribute(location, attribute.numComponents, attribute.type, attribute.normalized,
attributes.vertexSize, attribute.offset);
}
} else {
for (int i = 0; i < numAttributes; i++) {
final VertexAttribute attribute = attributes.get(i);
final int location = locations[i];
if (location < 0) continue;
shader.enableVertexAttribute(location);
shader.setVertexAttribute(location, attribute.numComponents, attribute.type, attribute.normalized,
attributes.vertexSize, attribute.offset);
}
}
isBound = true;
}
/** Unbinds this VertexBufferObject.
*
* @param shader the shader */
@Override
public void unbind (final ShaderProgram shader) {
unbind(shader, null);
}
@Override
public void unbind (final ShaderProgram shader, final int[] locations) {
final GL20 gl = Gdx.gl20;
final int numAttributes = attributes.size();
if (locations == null) {
for (int i = 0; i < numAttributes; i++) {
shader.disableVertexAttribute(attributes.get(i).alias);
}
} else {
for (int i = 0; i < numAttributes; i++) {
final int location = locations[i];
if (location >= 0) shader.disableVertexAttribute(location);
}
}
gl.glBindBuffer(GL20.GL_ARRAY_BUFFER, 0);
isBound = false;
}
/** Invalidates the VertexBufferObject so a new OpenGL buffer handle is created. Use this in case of a context loss. */
@Override
public void invalidate () {
bufferHandle = Gdx.gl20.glGenBuffer();
isDirty = true;
}
/** Disposes of all resources this VertexBufferObject uses. */
@Override
public void dispose () {
GL20 gl = Gdx.gl20;
gl.glBindBuffer(GL20.GL_ARRAY_BUFFER, 0);
gl.glDeleteBuffer(bufferHandle);
bufferHandle = 0;
if (ownsBuffer) BufferUtils.disposeUnsafeByteBuffer(byteBuffer);
}
}