/*******************************************************************************
* 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.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.graphics.VertexAttributes.Usage;
import com.badlogic.gdx.utils.BufferUtils;
/** <p>
* A {@link VertexData} implementation based on OpenGL vertex buffer objects.
* </p>
*
* <p>
* If the OpenGL ES context was lost you can call {@link #invalidate()} to recreate a new OpenGL vertex buffer object. This class
* can be used seamlessly with OpenGL ES 1.x and 2.0.
* </p>
*
* <p>
* In case OpenGL ES 2.0 is used in the application the data is bound via glVertexAttribPointer() according to the attribute
* aliases specified via {@link VertexAttributes} in the constructor.
* </p>
*
* <p>
* Uses indirect Buffers on Android 1.5/1.6 to fix GC invocation due to leaking PlatformAddress instances.
* </p>
*
* <p>
* VertexBufferObjects must be disposed via the {@link #dispose()} method when no longer needed
* </p>
*
* @author mzechner, Dave Clayton <contact@redskyforge.com> */
public class VertexBufferObject implements VertexData {
final VertexAttributes attributes;
final FloatBuffer buffer;
int bufferHandle;
final boolean isStatic;
final 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) {
this.isStatic = isStatic;
this.attributes = attributes;
buffer = BufferUtils.newFloatBuffer(this.attributes.vertexSize / 4 * numVertices);
buffer.flip();
bufferHandle = Gdx.gl20.glGenBuffer();
usage = isStatic ? GL20.GL_STATIC_DRAW : GL20.GL_DYNAMIC_DRAW;
}
@Override
public VertexAttributes getAttributes () {
return attributes;
}
@Override
public int getNumVertices () {
return buffer.limit() / (attributes.vertexSize / 4);
}
@Override
public int getNumMaxVertices () {
return buffer.capacity() / (attributes.vertexSize / 4);
}
@Override
public FloatBuffer getBuffer () {
isDirty = true;
return buffer;
}
private void bufferChanged() {
if (isBound) {
Gdx.gl20.glBufferData(GL20.GL_ARRAY_BUFFER, buffer.limit(), buffer, usage);
isDirty = false;
}
}
@Override
public void setVertices (float[] vertices, int offset, int count) {
isDirty = true;
BufferUtils.copy(vertices, buffer, 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 = buffer.position();
buffer.position(targetOffset);
BufferUtils.copy(vertices, sourceOffset, count, buffer);
buffer.position(pos);
bufferChanged();
}
/** Binds this VertexBufferObject for rendering via glDrawArrays or glDrawElements
*
* @param shader the shader */
/** 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) {
gl.glBufferData(GL20.GL_ARRAY_BUFFER, buffer.limit(), buffer, 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);
if (attribute.usage == Usage.ColorPacked)
shader.setVertexAttribute(location, attribute.numComponents, GL20.GL_UNSIGNED_BYTE, true, attributes.vertexSize,
attribute.offset);
else
shader.setVertexAttribute(location, attribute.numComponents, GL20.GL_FLOAT, false, 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);
if (attribute.usage == Usage.ColorPacked)
shader.setVertexAttribute(location, attribute.numComponents, GL20.GL_UNSIGNED_BYTE, true, attributes.vertexSize,
attribute.offset);
else
shader.setVertexAttribute(location, attribute.numComponents, GL20.GL_FLOAT, false, 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. */
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;
}
}