GrTypes.h

/*
 * Copyright 2010 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef GrTypes_DEFINED
#define GrTypes_DEFINED

#include "SkMath.h"
#include "SkTypes.h"
#include "GrConfig.h"


#define GR_MAKE_BITFIELD_OPS(X) \
    inline X operator | (X a, X b) { \
        return (X) (+a | +b); \
    } \
    inline X& operator |= (X& a, X b) { \
        return (a = a | b); \
    } \
    \
    inline X operator & (X a, X b) { \
        return (X) (+a & +b); \
    } \
    template <typename T> \
    inline X operator & (T a, X b) { \
        return (X) (+a & +b); \
    } \
    template <typename T> \
    inline X operator & (X a, T b) { \
        return (X) (+a & +b); \
    } \

#define GR_DECL_BITFIELD_OPS_FRIENDS(X) \
    friend X operator | (X a, X b); \
    friend X& operator |= (X& a, X b); \
    \
    friend X operator & (X a, X b); \
    \
    template <typename T> \
    friend X operator & (T a, X b); \
    \
    template <typename T> \
    friend X operator & (X a, T b); \


#define GR_MAKE_BITFIELD_CLASS_OPS(X) \
    inline X operator | (X a, X b) { \
        return (X) ((int)a | (int)b); \
    } \
    inline X& operator |= (X& a, X b) { \
        return (a = a | b); \
    } \
    inline bool operator & (X a, X b) { \
        return SkToBool((int)a & (int)b); \
    }

#define GR_DECL_BITFIELD_CLASS_OPS_FRIENDS(X) \
    friend X operator | (X a, X b); \
    friend X& operator |= (X& a, X b); \
    friend bool operator & (X a, X b);


// compile time versions of min/max
#define GR_CT_MAX(a, b) (((b) < (a)) ? (a) : (b))
#define GR_CT_MIN(a, b) (((b) < (a)) ? (b) : (a))

static inline int32_t GrIDivRoundUp(int x, int y) {
    SkASSERT(y > 0);
    return (x + (y-1)) / y;
}
static inline uint32_t GrUIDivRoundUp(uint32_t x, uint32_t y) {
    return (x + (y-1)) / y;
}
static inline size_t GrSizeDivRoundUp(size_t x, size_t y) {
    return (x + (y-1)) / y;
}

// compile time, evaluates Y multiple times
#define GR_CT_DIV_ROUND_UP(X, Y) (((X) + ((Y)-1)) / (Y))

static inline uint32_t GrUIAlignUp(uint32_t x, uint32_t alignment) {
    return GrUIDivRoundUp(x, alignment) * alignment;
}
static inline size_t GrSizeAlignUp(size_t x, size_t alignment) {
    return GrSizeDivRoundUp(x, alignment) * alignment;
}

// compile time, evaluates A multiple times
#define GR_CT_ALIGN_UP(X, A) (GR_CT_DIV_ROUND_UP((X),(A)) * (A))

static inline uint32_t GrUIAlignUpPad(uint32_t x, uint32_t alignment) {
    return (alignment - x % alignment) % alignment;
}
static inline size_t GrSizeAlignUpPad(size_t x, size_t alignment) {
    return (alignment - x % alignment) % alignment;
}

static inline uint32_t GrUIAlignDown(uint32_t x, uint32_t alignment) {
    return (x / alignment) * alignment;
}
static inline size_t GrSizeAlignDown(size_t x, uint32_t alignment) {
    return (x / alignment) * alignment;
}


enum GrBackend {
    kOpenGL_GrBackend,
    kVulkan_GrBackend,

    kLast_GrBackend = kVulkan_GrBackend
};
const int kBackendCount = kLast_GrBackend + 1;

typedef intptr_t GrBackendContext;


enum GrPrimitiveType {
    kTriangles_GrPrimitiveType,
    kTriangleStrip_GrPrimitiveType,
    kTriangleFan_GrPrimitiveType,
    kPoints_GrPrimitiveType,
    kLines_GrPrimitiveType,     // 1 pix wide only
    kLineStrip_GrPrimitiveType, // 1 pix wide only
    kLast_GrPrimitiveType = kLineStrip_GrPrimitiveType
};

static inline bool GrIsPrimTypeLines(GrPrimitiveType type) {
    return kLines_GrPrimitiveType == type || kLineStrip_GrPrimitiveType == type;
}

static inline bool GrIsPrimTypeTris(GrPrimitiveType type) {
    return kTriangles_GrPrimitiveType == type     ||
           kTriangleStrip_GrPrimitiveType == type ||
           kTriangleFan_GrPrimitiveType == type;
}

enum GrMaskFormat {
    kA8_GrMaskFormat,    
    kA565_GrMaskFormat,  
    kARGB_GrMaskFormat,  

    kLast_GrMaskFormat = kARGB_GrMaskFormat
};
static const int kMaskFormatCount = kLast_GrMaskFormat + 1;

static inline int GrMaskFormatBytesPerPixel(GrMaskFormat format) {
    SkASSERT(format < kMaskFormatCount);
    // kA8   (0) -> 1
    // kA565 (1) -> 2
    // kARGB (2) -> 4
    static const int sBytesPerPixel[] = { 1, 2, 4 };
    static_assert(SK_ARRAY_COUNT(sBytesPerPixel) == kMaskFormatCount, "array_size_mismatch");
    static_assert(kA8_GrMaskFormat == 0, "enum_order_dependency");
    static_assert(kA565_GrMaskFormat == 1, "enum_order_dependency");
    static_assert(kARGB_GrMaskFormat == 2, "enum_order_dependency");

    return sBytesPerPixel[(int) format];
}

enum GrPixelConfig {
    kUnknown_GrPixelConfig,
    kAlpha_8_GrPixelConfig,
    kIndex_8_GrPixelConfig,
    kRGB_565_GrPixelConfig,
    kRGBA_4444_GrPixelConfig,
    kRGBA_8888_GrPixelConfig,
    kBGRA_8888_GrPixelConfig,
    kSRGBA_8888_GrPixelConfig,
    kSBGRA_8888_GrPixelConfig,
    kETC1_GrPixelConfig,
    kLATC_GrPixelConfig,
    kR11_EAC_GrPixelConfig,

    kASTC_12x12_GrPixelConfig,

    kRGBA_float_GrPixelConfig,

    kAlpha_half_GrPixelConfig,

    kRGBA_half_GrPixelConfig,

    kLast_GrPixelConfig = kRGBA_half_GrPixelConfig
};
static const int kGrPixelConfigCnt = kLast_GrPixelConfig + 1;

// Aliases for pixel configs that match skia's byte order.
#ifndef SK_CPU_LENDIAN
    #error "Skia gpu currently assumes little endian"
#endif
#if SK_PMCOLOR_BYTE_ORDER(B,G,R,A)
    static const GrPixelConfig kSkia8888_GrPixelConfig = kBGRA_8888_GrPixelConfig;
    static const GrPixelConfig kSkiaGamma8888_GrPixelConfig = kSBGRA_8888_GrPixelConfig;
#elif SK_PMCOLOR_BYTE_ORDER(R,G,B,A)
    static const GrPixelConfig kSkia8888_GrPixelConfig = kRGBA_8888_GrPixelConfig;
    static const GrPixelConfig kSkiaGamma8888_GrPixelConfig = kSRGBA_8888_GrPixelConfig;
#else
    #error "SK_*32_SHIFT values must correspond to GL_BGRA or GL_RGBA format."
#endif

// Returns true if the pixel config is a GPU-specific compressed format
// representation.
static inline bool GrPixelConfigIsCompressed(GrPixelConfig config) {
    switch (config) {
        case kIndex_8_GrPixelConfig:
        case kETC1_GrPixelConfig:
        case kLATC_GrPixelConfig:
        case kR11_EAC_GrPixelConfig:
        case kASTC_12x12_GrPixelConfig:
            return true;
        default:
            return false;
    }
}

static inline GrPixelConfig GrMakePixelConfigUncompressed(GrPixelConfig config) {
    switch (config) {
        case kIndex_8_GrPixelConfig:
        case kETC1_GrPixelConfig:
        case kASTC_12x12_GrPixelConfig:
            return kRGBA_8888_GrPixelConfig;
        case kLATC_GrPixelConfig:
        case kR11_EAC_GrPixelConfig:
            return kAlpha_8_GrPixelConfig;
        default:
            SkASSERT(!GrPixelConfigIsCompressed(config));
            return config;
    }
}

// Returns true if the pixel config is 32 bits per pixel
static inline bool GrPixelConfigIs8888(GrPixelConfig config) {
    switch (config) {
        case kRGBA_8888_GrPixelConfig:
        case kBGRA_8888_GrPixelConfig:
        case kSRGBA_8888_GrPixelConfig:
        case kSBGRA_8888_GrPixelConfig:
            return true;
        default:
            return false;
    }
}

// Returns true if the color (non-alpha) components represent sRGB values. It does NOT indicate that
// all three color components are present in the config or anything about their order.
static inline bool GrPixelConfigIsSRGB(GrPixelConfig config) {
    switch (config) {
        case kSRGBA_8888_GrPixelConfig:
        case kSBGRA_8888_GrPixelConfig:
            return true;
        default:
            return false;
    }
}

// Takes a config and returns the equivalent config with the R and B order
// swapped if such a config exists. Otherwise, kUnknown_GrPixelConfig
static inline GrPixelConfig GrPixelConfigSwapRAndB(GrPixelConfig config) {
    switch (config) {
        case kBGRA_8888_GrPixelConfig:
            return kRGBA_8888_GrPixelConfig;
        case kRGBA_8888_GrPixelConfig:
            return kBGRA_8888_GrPixelConfig;
        case kSBGRA_8888_GrPixelConfig:
            return kSRGBA_8888_GrPixelConfig;
        case kSRGBA_8888_GrPixelConfig:
            return kSBGRA_8888_GrPixelConfig;
        default:
            return kUnknown_GrPixelConfig;
    }
}

static inline size_t GrBytesPerPixel(GrPixelConfig config) {
    SkASSERT(!GrPixelConfigIsCompressed(config));
    switch (config) {
        case kAlpha_8_GrPixelConfig:
            return 1;
        case kRGB_565_GrPixelConfig:
        case kRGBA_4444_GrPixelConfig:
        case kAlpha_half_GrPixelConfig:
            return 2;
        case kRGBA_8888_GrPixelConfig:
        case kBGRA_8888_GrPixelConfig:
        case kSRGBA_8888_GrPixelConfig:
        case kSBGRA_8888_GrPixelConfig:
            return 4;
        case kRGBA_half_GrPixelConfig:
            return 8;
        case kRGBA_float_GrPixelConfig:
            return 16;
        default:
            return 0;
    }
}

static inline bool GrPixelConfigIsOpaque(GrPixelConfig config) {
    switch (config) {
        case kETC1_GrPixelConfig:
        case kRGB_565_GrPixelConfig:
            return true;
        default:
            return false;
    }
}

static inline bool GrPixelConfigIsAlphaOnly(GrPixelConfig config) {
    switch (config) {
        case kR11_EAC_GrPixelConfig:
        case kLATC_GrPixelConfig:
        case kASTC_12x12_GrPixelConfig:
        case kAlpha_8_GrPixelConfig:
        case kAlpha_half_GrPixelConfig:
            return true;
        default:
            return false;
    }
}

static inline bool GrPixelConfigIsFloatingPoint(GrPixelConfig config) {
    switch (config) {
        case kRGBA_float_GrPixelConfig:
        case kAlpha_half_GrPixelConfig:
        case kRGBA_half_GrPixelConfig:
            return true;
        default:
            return false;
    }
}

enum GrSurfaceFlags {
    kNone_GrSurfaceFlags            = 0x0,
    kRenderTarget_GrSurfaceFlag     = 0x1,
    kZeroCopy_GrSurfaceFlag         = 0x2,
    kCheckAllocation_GrSurfaceFlag  = 0x4,
};

GR_MAKE_BITFIELD_OPS(GrSurfaceFlags)

// opaque type for 3D API object handles
typedef intptr_t GrBackendObject;

enum GrSurfaceOrigin {
    kDefault_GrSurfaceOrigin,         // DEPRECATED; to be removed
    kTopLeft_GrSurfaceOrigin,
    kBottomLeft_GrSurfaceOrigin,
};

struct GrMipLevel {
    const void* fPixels;
    size_t fRowBytes;
};

struct GrSurfaceDesc {
    GrSurfaceDesc()
    : fFlags(kNone_GrSurfaceFlags)
    , fOrigin(kDefault_GrSurfaceOrigin)
    , fWidth(0)
    , fHeight(0)
    , fConfig(kUnknown_GrPixelConfig)
    , fSampleCnt(0)
    , fIsMipMapped(false) {
    }

    GrSurfaceFlags         fFlags;  
    GrSurfaceOrigin        fOrigin; 
    int                    fWidth;  
    int                    fHeight; 

    GrPixelConfig          fConfig;

    int                    fSampleCnt;
    bool                   fIsMipMapped; 
};

// Legacy alias
typedef GrSurfaceDesc GrTextureDesc;

enum GrClipType {
    kRect_ClipType,
    kPath_ClipType
};



enum GrWrapOwnership {
    kBorrow_GrWrapOwnership,

    kAdopt_GrWrapOwnership,
};

enum GrBackendTextureFlags {
    kNone_GrBackendTextureFlag             = 0,
    kRenderTarget_GrBackendTextureFlag     = kRenderTarget_GrSurfaceFlag,
};
GR_MAKE_BITFIELD_OPS(GrBackendTextureFlags)

struct GrBackendTextureDesc {
    GrBackendTextureDesc() { memset(this, 0, sizeof(*this)); }
    GrBackendTextureFlags           fFlags;
    GrSurfaceOrigin                 fOrigin;
    int                             fWidth;         //<! width in pixels
    int                             fHeight;        //<! height in pixels
    GrPixelConfig                   fConfig;        //<! color format
    int                             fSampleCnt;
    GrBackendObject                 fTextureHandle;
};


struct GrBackendRenderTargetDesc {
    GrBackendRenderTargetDesc() { memset(this, 0, sizeof(*this)); }
    int                             fWidth;         //<! width in pixels
    int                             fHeight;        //<! height in pixels
    GrPixelConfig                   fConfig;        //<! color format
    GrSurfaceOrigin                 fOrigin;        //<! pixel origin
    int                             fSampleCnt;
    int                             fStencilBits;
    GrBackendObject                 fRenderTargetHandle;
};

enum GrGLBackendState {
    kRenderTarget_GrGLBackendState     = 1 << 0,
    kTextureBinding_GrGLBackendState   = 1 << 1,
    // View state stands for scissor and viewport
    kView_GrGLBackendState             = 1 << 2,
    kBlend_GrGLBackendState            = 1 << 3,
    kMSAAEnable_GrGLBackendState       = 1 << 4,
    kVertex_GrGLBackendState           = 1 << 5,
    kStencil_GrGLBackendState          = 1 << 6,
    kPixelStore_GrGLBackendState       = 1 << 7,
    kProgram_GrGLBackendState          = 1 << 8,
    kFixedFunction_GrGLBackendState    = 1 << 9,
    kMisc_GrGLBackendState             = 1 << 10,
    kPathRendering_GrGLBackendState    = 1 << 11,
    kALL_GrGLBackendState              = 0xffff
};

static inline size_t GrCompressedFormatDataSize(GrPixelConfig config,
                                                int width, int height) {
    SkASSERT(GrPixelConfigIsCompressed(config));
    static const int kGrIndex8TableSize = 256 * 4; // 4 == sizeof(GrColor)

    switch (config) {
        case kIndex_8_GrPixelConfig:
            return width * height + kGrIndex8TableSize;
        case kR11_EAC_GrPixelConfig:
        case kLATC_GrPixelConfig:
        case kETC1_GrPixelConfig:
            SkASSERT((width & 3) == 0);
            SkASSERT((height & 3) == 0);
            return (width >> 2) * (height >> 2) * 8;

        case kASTC_12x12_GrPixelConfig:
            SkASSERT((width % 12) == 0);
            SkASSERT((height % 12) == 0);
            return (width / 12) * (height / 12) * 16;

        default:
            SkFAIL("Unknown compressed pixel config");
            return 4 * width * height;
    }
}

static const uint32_t kAll_GrBackendState = 0xffffffff;

#endif