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Diffstat (limited to 'gpu/include/GrTexture.h')
| -rw-r--r-- | gpu/include/GrTexture.h | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/gpu/include/GrTexture.h b/gpu/include/GrTexture.h new file mode 100644 index 0000000..666aa57 --- /dev/null +++ b/gpu/include/GrTexture.h @@ -0,0 +1,206 @@ +/* + Copyright 2011 Google Inc. + + 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. + */ + + +#ifndef GrTexture_DEFINED +#define GrTexture_DEFINED + +#include "GrRefCnt.h" +#include "GrClip.h" + +class GrTexture; + +/** + * GrRenderTarget represents a 2D buffer of pixels that can be rendered to. + * A context's render target is set by setRenderTarget(). Render targets are + * created by a createTexture with the kRenderTarget_TextureFlag flag. + * Additionally, GrContext provides methods for creating GrRenderTargets + * that wrap externally created render targets. + */ +class GrRenderTarget : public GrRefCnt { +public: + /** + * @return the width of the rendertarget + */ + int width() const { return fWidth; } + /** + * @return the height of the rendertarget + */ + int height() const { return fHeight; } + + /** + * @return the number of stencil bits in the rendertarget + */ + int stencilBits() const { return fStencilBits; } + + /** + * @return the texture associated with the rendertarget, may be NULL. + */ + GrTexture* asTexture() {return fTexture;} + +protected: + GrRenderTarget(GrTexture* texture, + int width, + int height, + int stencilBits) + : fTexture(texture), + fWidth(width), + fHeight(height), + fStencilBits(stencilBits) {} + + + GrTexture* fTexture; + int fWidth; + int fHeight; + int fStencilBits; + +private: + // GrGpu keeps a cached clip in the render target to avoid redundantly + // rendering the clip into the same stencil buffer. + friend class GrGpu; + GrClip fLastStencilClip; + + typedef GrRefCnt INHERITED; +}; + +class GrTexture : public GrRefCnt { +public: + enum PixelConfig { + kUnknown_PixelConfig, + kAlpha_8_PixelConfig, + kIndex_8_PixelConfig, + kRGB_565_PixelConfig, + kRGBA_4444_PixelConfig, //!< premultiplied + kRGBA_8888_PixelConfig, //!< premultiplied + kRGBX_8888_PixelConfig, //!< treat the alpha channel as opaque + }; + static size_t BytesPerPixel(PixelConfig); + static bool PixelConfigIsOpaque(PixelConfig); + +protected: + GrTexture(int width, + int height, + PixelConfig config) : + fWidth(width), + fHeight(height), + fConfig(config) { + // only make sense if alloc size is pow2 + fShiftFixedX = 31 - Gr_clz(fWidth); + fShiftFixedY = 31 - Gr_clz(fHeight); + } +public: + virtual ~GrTexture(); + + /** + * Retrieves the width of the texture. + * + * @return the width in texels + */ + int width() const { return fWidth; } + /** + * Retrieves the height of the texture. + * + * @return the height in texels + */ + int height() const { return fHeight; } + + /** + * Convert from texels to normalized texture coords for POT textures + * only. + */ + GrFixed normalizeFixedX(GrFixed x) const { GrAssert(GrIsPow2(fWidth)); + return x >> fShiftFixedX; } + GrFixed normalizeFixedY(GrFixed y) const { GrAssert(GrIsPow2(fHeight)); + return y >> fShiftFixedY; } + + /** + * Retrieves the pixel config specified when the texture was created. + */ + PixelConfig config() const { return fConfig; } + + /** + * Approximate number of bytes used by the texture + */ + size_t sizeInBytes() const { + return fWidth * fHeight * BytesPerPixel(fConfig); + } + + /** + * Updates a subrectangle of texels in the texture. + * + * @param x left edge of rectangle to update + * @param y top edge of rectangle to update + * @param width width of rectangle to update + * @param height height of rectangle to update + * @param srcData width*height texels of data in same format that was used + * at texture creation. + */ + virtual void uploadTextureData(uint32_t x, + uint32_t y, + uint32_t width, + uint32_t height, + const void* srcData) = 0; + /** + * Indicates that GPU context in which this texture was created is destroyed + * and that Ganesh should not attempt to free the texture with the + * underlying API. + */ + virtual void abandon() = 0; + + /** + * Retrieves the render target underlying this texture that can be passed to + * GrGpu::setRenderTarget(). + * + * @return handle to render target or undefined if the texture is not a + * render target + */ + virtual GrRenderTarget* asRenderTarget() = 0; + + /** + * Removes the reference on the associated GrRenderTarget held by this + * texture. Afterwards asRenderTarget() will return NULL. The + * GrRenderTarget survives the release if another ref is held on it. + */ + virtual void releaseRenderTarget() = 0; + + /** + * Return the native ID or handle to the texture, depending on the + * platform. e.g. on opengl, return the texture ID. + */ + virtual intptr_t getTextureHandle() = 0; + +#if GR_DEBUG + void validate() const { + this->INHERITED::validate(); + } +#else + void validate() const {} +#endif + +private: + int fWidth; + int fHeight; + // these two shift a fixed-point value into normalized coordinates + // for this texture if the texture is power of two sized. + int fShiftFixedX; + int fShiftFixedY; + PixelConfig fConfig; + + typedef GrRefCnt INHERITED; +}; + +#endif + |