1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/skia/trunk/include/gpu/GrRenderTarget.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,171 @@
1.4 +/*
1.5 + * Copyright 2011 Google Inc.
1.6 + *
1.7 + * Use of this source code is governed by a BSD-style license that can be
1.8 + * found in the LICENSE file.
1.9 + */
1.10 +
1.11 +#ifndef GrRenderTarget_DEFINED
1.12 +#define GrRenderTarget_DEFINED
1.13 +
1.14 +#include "GrSurface.h"
1.15 +#include "SkRect.h"
1.16 +
1.17 +class GrStencilBuffer;
1.18 +class GrTexture;
1.19 +
1.20 +/**
1.21 + * GrRenderTarget represents a 2D buffer of pixels that can be rendered to.
1.22 + * A context's render target is set by setRenderTarget(). Render targets are
1.23 + * created by a createTexture with the kRenderTarget_TextureFlag flag.
1.24 + * Additionally, GrContext provides methods for creating GrRenderTargets
1.25 + * that wrap externally created render targets.
1.26 + */
1.27 +class GrRenderTarget : public GrSurface {
1.28 +public:
1.29 + SK_DECLARE_INST_COUNT(GrRenderTarget)
1.30 +
1.31 + // GrResource overrides
1.32 + virtual size_t sizeInBytes() const SK_OVERRIDE;
1.33 +
1.34 + // GrSurface overrides
1.35 + /**
1.36 + * @return the texture associated with the render target, may be NULL.
1.37 + */
1.38 + virtual GrTexture* asTexture() SK_OVERRIDE { return fTexture; }
1.39 + virtual const GrTexture* asTexture() const SK_OVERRIDE { return fTexture; }
1.40 +
1.41 + /**
1.42 + * @return this render target.
1.43 + */
1.44 + virtual GrRenderTarget* asRenderTarget() SK_OVERRIDE { return this; }
1.45 + virtual const GrRenderTarget* asRenderTarget() const SK_OVERRIDE {
1.46 + return this;
1.47 + }
1.48 +
1.49 + virtual bool readPixels(int left, int top, int width, int height,
1.50 + GrPixelConfig config,
1.51 + void* buffer,
1.52 + size_t rowBytes = 0,
1.53 + uint32_t pixelOpsFlags = 0) SK_OVERRIDE;
1.54 +
1.55 + virtual void writePixels(int left, int top, int width, int height,
1.56 + GrPixelConfig config,
1.57 + const void* buffer,
1.58 + size_t rowBytes = 0,
1.59 + uint32_t pixelOpsFlags = 0) SK_OVERRIDE;
1.60 +
1.61 + // GrRenderTarget
1.62 + /**
1.63 + * If this RT is multisampled, this is the multisample buffer
1.64 + * @return the 3D API's handle to this object (e.g. FBO ID in OpenGL)
1.65 + */
1.66 + virtual GrBackendObject getRenderTargetHandle() const = 0;
1.67 +
1.68 + /**
1.69 + * If this RT is multisampled, this is the buffer it is resolved to.
1.70 + * Otherwise, same as getRenderTargetHandle().
1.71 + * (In GL a separate FBO ID is used for the MSAA and resolved buffers)
1.72 + * @return the 3D API's handle to this object (e.g. FBO ID in OpenGL)
1.73 + */
1.74 + virtual GrBackendObject getRenderTargetResolvedHandle() const = 0;
1.75 +
1.76 + /**
1.77 + * @return true if the surface is multisampled, false otherwise
1.78 + */
1.79 + bool isMultisampled() const { return 0 != fDesc.fSampleCnt; }
1.80 +
1.81 + /**
1.82 + * @return the number of samples-per-pixel or zero if non-MSAA.
1.83 + */
1.84 + int numSamples() const { return fDesc.fSampleCnt; }
1.85 +
1.86 + /**
1.87 + * Call to indicate the multisample contents were modified such that the
1.88 + * render target needs to be resolved before it can be used as texture. Gr
1.89 + * tracks this for its own drawing and thus this only needs to be called
1.90 + * when the render target has been modified outside of Gr. This has no
1.91 + * effect on wrapped backend render targets.
1.92 + *
1.93 + * @param rect a rect bounding the area needing resolve. NULL indicates
1.94 + * the whole RT needs resolving.
1.95 + */
1.96 + void flagAsNeedingResolve(const SkIRect* rect = NULL);
1.97 +
1.98 + /**
1.99 + * Call to override the region that needs to be resolved.
1.100 + */
1.101 + void overrideResolveRect(const SkIRect rect);
1.102 +
1.103 + /**
1.104 + * Call to indicate that GrRenderTarget was externally resolved. This may
1.105 + * allow Gr to skip a redundant resolve step.
1.106 + */
1.107 + void flagAsResolved() { fResolveRect.setLargestInverted(); }
1.108 +
1.109 + /**
1.110 + * @return true if the GrRenderTarget requires MSAA resolving
1.111 + */
1.112 + bool needsResolve() const { return !fResolveRect.isEmpty(); }
1.113 +
1.114 + /**
1.115 + * Returns a rect bounding the region needing resolving.
1.116 + */
1.117 + const SkIRect& getResolveRect() const { return fResolveRect; }
1.118 +
1.119 + /**
1.120 + * If the render target is multisampled this will perform a multisample
1.121 + * resolve. Any pending draws to the target are first flushed. This only
1.122 + * applies to render targets that are associated with GrTextures. After the
1.123 + * function returns the GrTexture will contain the resolved pixels.
1.124 + */
1.125 + void resolve();
1.126 +
1.127 + // a MSAA RT may require explicit resolving , it may auto-resolve (e.g. FBO
1.128 + // 0 in GL), or be unresolvable because the client didn't give us the
1.129 + // resolve destination.
1.130 + enum ResolveType {
1.131 + kCanResolve_ResolveType,
1.132 + kAutoResolves_ResolveType,
1.133 + kCantResolve_ResolveType,
1.134 + };
1.135 + virtual ResolveType getResolveType() const = 0;
1.136 +
1.137 + /**
1.138 + * GrStencilBuffer is not part of the public API.
1.139 + */
1.140 + GrStencilBuffer* getStencilBuffer() const { return fStencilBuffer; }
1.141 + void setStencilBuffer(GrStencilBuffer* stencilBuffer);
1.142 +
1.143 +protected:
1.144 + GrRenderTarget(GrGpu* gpu,
1.145 + bool isWrapped,
1.146 + GrTexture* texture,
1.147 + const GrTextureDesc& desc)
1.148 + : INHERITED(gpu, isWrapped, desc)
1.149 + , fStencilBuffer(NULL)
1.150 + , fTexture(texture) {
1.151 + fResolveRect.setLargestInverted();
1.152 + }
1.153 +
1.154 + // override of GrResource
1.155 + virtual void onAbandon() SK_OVERRIDE;
1.156 + virtual void onRelease() SK_OVERRIDE;
1.157 +
1.158 +private:
1.159 + friend class GrTexture;
1.160 + // called by ~GrTexture to remove the non-ref'ed back ptr.
1.161 + void owningTextureDestroyed() {
1.162 + SkASSERT(NULL != fTexture);
1.163 + fTexture = NULL;
1.164 + }
1.165 +
1.166 + GrStencilBuffer* fStencilBuffer;
1.167 + GrTexture* fTexture; // not ref'ed
1.168 +
1.169 + SkIRect fResolveRect;
1.170 +
1.171 + typedef GrSurface INHERITED;
1.172 +};
1.173 +
1.174 +#endif
