/*******************************************************************************
* 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.ByteBuffer;
import java.nio.IntBuffer;
import java.nio.ShortBuffer;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.graphics.GL11;
import com.badlogic.gdx.graphics.GL20;
import com.badlogic.gdx.utils.BufferUtils;
import com.badlogic.gdx.utils.GdxRuntimeException;
/**
* <p>
* In IndexBufferObject wraps OpenGL's index buffer functionality to be used in conjunction with VBOs. This class can be
* seamlessly used with OpenGL ES 1.x and 2.0.
* </p>
*
* <p>
* Uses indirect Buffers on Android 1.5/1.6 to fix GC invocation due to leaking PlatformAddress instances.
* </p>
*
* <p>
* You can also use this to store indices for vertex arrays. Do not call {@link #bind()} or {@link #unbind()} in this
* case but rather use {@link #getBuffer()} to use the buffer directly with glDrawElements. You must also create the
* IndexBufferObject with the second constructor and specify isDirect as true as glDrawElements in conjunction with
* vertex arrays needs direct buffers.
* </p>
*
* <p>
* VertexBufferObjects must be disposed via the {@link #dispose()} method when no longer needed
* </p>
*
* @author mzechner
*/
public class IndexBufferObject implements IndexData {
final static IntBuffer tmpHandle = BufferUtils.newIntBuffer(1);
ShortBuffer buffer;
ByteBuffer byteBuffer;
int bufferHandle;
final boolean isDirect;
boolean isDirty = true;
boolean isBound = false;
final int usage;
/**
* Creates a new IndexBufferObject.
*
* @param isStatic
* whether the index buffer is static
* @param maxIndices
* the maximum number of indices this buffer can hold
*/
public IndexBufferObject(boolean isStatic, int maxIndices) {
// if (Gdx.app.getType() == ApplicationType.Android
// && Gdx.app.getVersion() < 5) {
// byteBuffer = ByteBuffer.allocate(maxIndices * 2);
// byteBuffer.order(ByteOrder.nativeOrder());
// isDirect = false;
// } else {
byteBuffer = BufferUtils.newUnsafeByteBuffer(maxIndices * 2);
isDirect = true;
// }
buffer = byteBuffer.asShortBuffer();
buffer.flip();
byteBuffer.flip();
bufferHandle = createBufferObject();
usage = isStatic ? GL11.GL_STATIC_DRAW : GL11.GL_DYNAMIC_DRAW;
}
/**
* Creates a new IndexBufferObject to be used with vertex arrays.
*
* @param maxIndices
* the maximum number of indices this buffer can hold
*/
public IndexBufferObject(int maxIndices) {
byteBuffer = BufferUtils.newUnsafeByteBuffer(maxIndices * 2);
this.isDirect = true;
buffer = byteBuffer.asShortBuffer();
buffer.flip();
byteBuffer.flip();
bufferHandle = createBufferObject();
usage = GL11.GL_STATIC_DRAW;
}
private int createBufferObject() {
if (Gdx.gl20 != null) {
Gdx.gl20.glGenBuffers(1, tmpHandle);
return tmpHandle.get(0);
} else if (Gdx.gl11 != null) {
Gdx.gl11.glGenBuffers(1, tmpHandle);
return tmpHandle.get(0);
} else {
throw new GdxRuntimeException("Can not use IndexBufferObject with GLES 1.0, need 1.1 or 2.0");
}
}
/** @return the number of indices currently stored in this buffer */
public int getNumIndices() {
return buffer.limit();
}
/** @return the maximum number of indices this IndexBufferObject can store. */
public int getNumMaxIndices() {
return buffer.capacity();
}
/**
* <p>
* Sets the indices of this IndexBufferObject, discarding the old indices. The count must equal the number of
* indices to be copied to this IndexBufferObject.
* </p>
*
* <p>
* This can be called in between calls to {@link #bind()} and {@link #unbind()}. The index data will be updated
* instantly.
* </p>
*
* @param indices
* the vertex data
* @param offset
* the offset to start copying the data from
* @param count
* the number of shorts to copy
*/
public void setIndices(short[] indices, int offset, int count) {
isDirty = true;
buffer.clear();
buffer.put(indices, offset, count);
buffer.flip();
byteBuffer.position(0);
byteBuffer.limit(count << 1);
if (isBound) {
if (Gdx.gl11 != null) {
GL11 gl = Gdx.gl11;
gl.glBufferData(GL11.GL_ELEMENT_ARRAY_BUFFER, byteBuffer.limit(), byteBuffer, usage);
} else if (Gdx.gl20 != null) {
GL20 gl = Gdx.gl20;
gl.glBufferData(GL20.GL_ELEMENT_ARRAY_BUFFER, byteBuffer.limit(), byteBuffer, usage);
}
isDirty = false;
}
}
/**
* <p>
* Returns the underlying ShortBuffer. If you modify the buffer contents they wil be uploaded on the call to
* {@link #bind()}. If you need immediate uploading use {@link #setIndices(short[], int, int)}.
* </p>
*
* @return the underlying short buffer.
*/
public ShortBuffer getBuffer() {
isDirty = true;
return buffer;
}
/** Binds this IndexBufferObject for rendering with glDrawElements. */
public void bind() {
if (bufferHandle == 0)
throw new GdxRuntimeException("No buffer allocated!");
if (Gdx.gl11 != null) {
GL11 gl = Gdx.gl11;
gl.glBindBuffer(GL11.GL_ELEMENT_ARRAY_BUFFER, bufferHandle);
if (isDirty) {
byteBuffer.limit(buffer.limit() * 2);
gl.glBufferData(GL11.GL_ELEMENT_ARRAY_BUFFER, byteBuffer.limit(), byteBuffer, usage);
isDirty = false;
}
} else {
GL20 gl = Gdx.gl20;
gl.glBindBuffer(GL20.GL_ELEMENT_ARRAY_BUFFER, bufferHandle);
if (isDirty) {
byteBuffer.limit(buffer.limit() * 2);
gl.glBufferData(GL20.GL_ELEMENT_ARRAY_BUFFER, byteBuffer.limit(), byteBuffer, usage);
isDirty = false;
}
}
isBound = true;
}
/** Unbinds this IndexBufferObject. */
public void unbind() {
if (Gdx.gl11 != null) {
Gdx.gl11.glBindBuffer(GL11.GL_ELEMENT_ARRAY_BUFFER, 0);
} else if (Gdx.gl20 != null) {
Gdx.gl20.glBindBuffer(GL11.GL_ELEMENT_ARRAY_BUFFER, 0);
}
isBound = false;
}
/** Invalidates the IndexBufferObject so a new OpenGL buffer handle is created. Use this in case of a context loss. */
public void invalidate() {
bufferHandle = createBufferObject();
isDirty = true;
}
/** Disposes this IndexBufferObject and all its associated OpenGL resources. */
public void dispose() {
if (Gdx.gl20 != null) {
tmpHandle.clear();
tmpHandle.put(bufferHandle);
tmpHandle.flip();
GL20 gl = Gdx.gl20;
gl.glBindBuffer(GL20.GL_ELEMENT_ARRAY_BUFFER, 0);
gl.glDeleteBuffers(1, tmpHandle);
bufferHandle = 0;
} else if (Gdx.gl11 != null) {
tmpHandle.clear();
tmpHandle.put(bufferHandle);
tmpHandle.flip();
GL11 gl = Gdx.gl11;
gl.glBindBuffer(GL11.GL_ELEMENT_ARRAY_BUFFER, 0);
gl.glDeleteBuffers(1, tmpHandle);
bufferHandle = 0;
}
BufferUtils.disposeUnsafeByteBuffer(byteBuffer);
}
}