1/*
2 * Copyright 2011 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8
9#ifndef GrGLRenderTarget_DEFINED
10#define GrGLRenderTarget_DEFINED
11
12#include "GrGLIRect.h"
13#include "GrRenderTarget.h"
14#include "SkScalar.h"
15
16class GrGpuGL;
17class GrGLTexture;
18class GrGLTexID;
19
20class GrGLRenderTarget : public GrRenderTarget {
21
22public:
23    // set fTexFBOID to this value to indicate that it is multisampled but
24    // Gr doesn't know how to resolve it.
25    enum { kUnresolvableFBOID = 0 };
26
27    struct Desc {
28        GrGLuint         fRTFBOID;
29        GrGLuint         fTexFBOID;
30        GrGLuint         fMSColorRenderbufferID;
31        bool             fIsWrapped;
32        GrPixelConfig    fConfig;
33        int              fSampleCnt;
34        GrSurfaceOrigin  fOrigin;
35        bool             fCheckAllocation;
36    };
37
38    // creates a GrGLRenderTarget associated with a texture
39    GrGLRenderTarget(GrGpuGL*          gpu,
40                     const Desc&       desc,
41                     const GrGLIRect&  viewport,
42                     GrGLTexID*        texID,
43                     GrGLTexture*      texture);
44
45    // creates an independent GrGLRenderTarget
46    GrGLRenderTarget(GrGpuGL*          gpu,
47                     const Desc&       desc,
48                     const GrGLIRect&  viewport);
49
50    virtual ~GrGLRenderTarget() { this->release(); }
51
52    void setViewport(const GrGLIRect& rect) { fViewport = rect; }
53    const GrGLIRect& getViewport() const { return fViewport; }
54
55    // The following two functions return the same ID when a
56    // texture/render target is multisampled, and different IDs when
57    // it is.
58    // FBO ID used to render into
59    GrGLuint renderFBOID() const { return fRTFBOID; }
60    // FBO ID that has texture ID attached.
61    GrGLuint textureFBOID() const { return fTexFBOID; }
62
63    // override of GrRenderTarget
64    virtual GrBackendObject getRenderTargetHandle() const {
65        return this->renderFBOID();
66    }
67    virtual GrBackendObject getRenderTargetResolvedHandle() const {
68        return this->textureFBOID();
69    }
70    virtual ResolveType getResolveType() const {
71
72        if (!this->isMultisampled() ||
73            fRTFBOID == fTexFBOID) {
74            // catches FBO 0 and non MSAA case
75            return kAutoResolves_ResolveType;
76        } else if (kUnresolvableFBOID == fTexFBOID) {
77            return kCantResolve_ResolveType;
78        } else {
79            return kCanResolve_ResolveType;
80        }
81    }
82
83protected:
84    // override of GrResource
85    virtual void onAbandon() SK_OVERRIDE;
86    virtual void onRelease() SK_OVERRIDE;
87
88private:
89    GrGLuint      fRTFBOID;
90    GrGLuint      fTexFBOID;
91
92    GrGLuint      fMSColorRenderbufferID;
93
94    // when we switch to this render target we want to set the viewport to
95    // only render to to content area (as opposed to the whole allocation) and
96    // we want the rendering to be at top left (GL has origin in bottom left)
97    GrGLIRect fViewport;
98
99    // non-NULL if this RT was created by Gr with an associated GrGLTexture.
100    SkAutoTUnref<GrGLTexID> fTexIDObj;
101
102    void init(const Desc& desc, const GrGLIRect& viewport, GrGLTexID* texID);
103
104    typedef GrRenderTarget INHERITED;
105};
106
107#endif
108