WebGLBuffer.h revision 65f03d4f644ce73618e5f4f50dd694b26f55ae12 
1/*
2 * Copyright (C) 2009 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef WebGLBuffer_h
27#define WebGLBuffer_h
28
29#include "ArrayBuffer.h"
30#include "WebGLObject.h"
31
32#include <wtf/PassRefPtr.h>
33#include <wtf/RefCounted.h>
34
35namespace WebCore {
36class ArrayBufferView;
37
38class WebGLBuffer : public WebGLObject {
39public:
40    virtual ~WebGLBuffer() { deleteObject(); }
41
42    static PassRefPtr<WebGLBuffer> create(WebGLRenderingContext*);
43
44    bool associateBufferData(GC3Dsizeiptr size);
45    bool associateBufferData(ArrayBuffer* array);
46    bool associateBufferData(ArrayBufferView* array);
47    bool associateBufferSubData(GC3Dintptr offset, ArrayBuffer* array);
48    bool associateBufferSubData(GC3Dintptr offset, ArrayBufferView* array);
49
50    GC3Dsizeiptr byteLength() const;
51    const ArrayBuffer* elementArrayBuffer() const { return m_elementArrayBuffer.get(); }
52
53    // Gets the cached max index for the given type. Returns -1 if
54    // none has been set.
55    int getCachedMaxIndex(GC3Denum type);
56    // Sets the cached max index for the given type.
57    void setCachedMaxIndex(GC3Denum type, int value);
58
59    GC3Denum getTarget() const { return m_target; }
60    void setTarget(GC3Denum);
61
62    bool hasEverBeenBound() const { return object() && m_target; }
63
64protected:
65    WebGLBuffer(WebGLRenderingContext*);
66
67    virtual void deleteObjectImpl(Platform3DObject o);
68
69private:
70    virtual bool isBuffer() const { return true; }
71
72    GC3Denum m_target;
73
74    RefPtr<ArrayBuffer> m_elementArrayBuffer;
75    GC3Dsizeiptr m_byteLength;
76
77    // Optimization for index validation. For each type of index
78    // (i.e., UNSIGNED_SHORT), cache the maximum index in the
79    // entire buffer.
80    //
81    // This is sufficient to eliminate a lot of work upon each
82    // draw call as long as all bound array buffers are at least
83    // that size.
84    struct MaxIndexCacheEntry {
85        GC3Denum type;
86        int maxIndex;
87    };
88    // OpenGL ES 2.0 only has two valid index types (UNSIGNED_BYTE
89    // and UNSIGNED_SHORT), but might as well leave open the
90    // possibility of adding others.
91    MaxIndexCacheEntry m_maxIndexCache[4];
92    unsigned int m_nextAvailableCacheEntry;
93
94    // Clears all of the cached max indices.
95    void clearCachedMaxIndices();
96
97    // Helper function called by the three associateBufferData().
98    bool associateBufferDataImpl(ArrayBuffer* array, GC3Dintptr byteOffset, GC3Dsizeiptr byteLength);
99    // Helper function called by the two associateBufferSubData().
100    bool associateBufferSubDataImpl(GC3Dintptr offset, ArrayBuffer* array, GC3Dintptr arrayByteOffset, GC3Dsizeiptr byteLength);
101};
102
103} // namespace WebCore
104
105#endif // WebGLBuffer_h
106