/*******************************************************************************
* 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.glview.libgdx.graphics.glutils;
import java.nio.ByteBuffer;
import java.nio.IntBuffer;
import java.nio.ShortBuffer;
import com.glview.App;
import com.glview.exception.GLViewRuntimeException;
import com.glview.hwui.GLId;
import com.glview.libgdx.graphics.opengl.GL20;
import com.glview.utils.BufferUtils;
/** <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.newByteBuffer(maxIndices * 2);
isDirect = true;
// }
buffer = byteBuffer.asShortBuffer();
buffer.flip();
byteBuffer.flip();
bufferHandle = createBufferObject();
usage = isStatic ? GL20.GL_STATIC_DRAW : GL20.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.newByteBuffer(maxIndices * 2);
this.isDirect = true;
buffer = byteBuffer.asShortBuffer();
buffer.flip();
byteBuffer.flip();
bufferHandle = createBufferObject();
usage = GL20.GL_STATIC_DRAW;
}
private int createBufferObject () {
int array[] = new int[1];
GLId.glGenBuffers(1, array, 0);
return array[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 (App.getGL20() != null) {
GL20 gl = App.getGL20();
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 GLViewRuntimeException("No buffer allocated!");
GL20 gl = App.getGL20();
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 (App.getGL20() != null) {
App.getGL20().glBindBuffer(GL20.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 (App.getGL20() != null) {
tmpHandle.clear();
tmpHandle.put(bufferHandle);
tmpHandle.flip();
GL20 gl = App.getGL20();
gl.glBindBuffer(GL20.GL_ELEMENT_ARRAY_BUFFER, 0);
gl.glDeleteBuffers(1, tmpHandle);
// if(Gdx.canvas != null){
// Gdx.canvas.deleteBuffer(bufferHandle);
// }
bufferHandle = 0;
}
// BufferUtils.disposeUnsafeByteBuffer(byteBuffer);
}
}