include/gpu/SkGr.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 SkGr_DEFINED
#define SkGr_DEFINED

#include "GrColor.h"
#include "GrSamplerParams.h"
#include "SkColor.h"
#include "SkColorPriv.h"
#include "SkFilterQuality.h"
#include "SkImageInfo.h"

class GrCaps;
class GrColorSpaceXform;
class GrContext;
class GrTexture;
class SkBitmap;

////////////////////////////////////////////////////////////////////////////////
// Sk to Gr Type conversions

static inline GrColor SkColorToPremulGrColor(SkColor c) {
    SkPMColor pm = SkPreMultiplyColor(c);
    unsigned r = SkGetPackedR32(pm);
    unsigned g = SkGetPackedG32(pm);
    unsigned b = SkGetPackedB32(pm);
    unsigned a = SkGetPackedA32(pm);
    return GrColorPackRGBA(r, g, b, a);
}

static inline GrColor SkColorToUnpremulGrColor(SkColor c) {
    unsigned r = SkColorGetR(c);
    unsigned g = SkColorGetG(c);
    unsigned b = SkColorGetB(c);
    unsigned a = SkColorGetA(c);
    return GrColorPackRGBA(r, g, b, a);
}

/** Transform an SkColor (sRGB bytes) to GrColor4f for the specified color space. */
GrColor4f SkColorToPremulGrColor4f(SkColor c, SkColorSpace* dstColorSpace);
GrColor4f SkColorToUnpremulGrColor4f(SkColor c, SkColorSpace* dstColorSpace);

/**
 * As above, but with explicit control over the linearization and gamut xform steps.
 * Typically used when you have easy access to a pre-computed xform.
 */
GrColor4f SkColorToPremulGrColor4f(SkColor c, bool gammaCorrect, GrColorSpaceXform* gamutXform);
GrColor4f SkColorToUnpremulGrColor4f(SkColor c, bool gammaCorrect, GrColorSpaceXform* gamutXform);

static inline GrColor SkColorToOpaqueGrColor(SkColor c) {
    unsigned r = SkColorGetR(c);
    unsigned g = SkColorGetG(c);
    unsigned b = SkColorGetB(c);
    return GrColorPackRGBA(r, g, b, 0xFF);
}

/** Replicates the SkColor's alpha to all four channels of the GrColor. */
static inline GrColor SkColorAlphaToGrColor(SkColor c) {
    U8CPU a = SkColorGetA(c);
    return GrColorPackRGBA(a, a, a, a);
}

static inline SkPMColor GrColorToSkPMColor(GrColor c) {
    GrColorIsPMAssert(c);
    return SkPackARGB32(GrColorUnpackA(c), GrColorUnpackR(c), GrColorUnpackG(c), GrColorUnpackB(c));
}

static inline GrColor SkPMColorToGrColor(SkPMColor c) {
    return GrColorPackRGBA(SkGetPackedR32(c), SkGetPackedG32(c), SkGetPackedB32(c),
                           SkGetPackedA32(c));
}

////////////////////////////////////////////////////////////////////////////////
/** Returns a texture representing the bitmap that is compatible with the GrSamplerParams. The
 *  texture is inserted into the cache (unless the bitmap is marked volatile) and can be
 *  retrieved again via this function.
 *  The 'scaleAdjust' in/out parameter will be updated to hold any rescaling that needs to be
 *  performed on the absolute texture coordinates (e.g., if the texture is resized out to
 *  the next power of two). It can be null if the caller is sure the bitmap won't be resized.
 */
GrTexture* GrRefCachedBitmapTexture(GrContext*, const SkBitmap&,
                                    const GrSamplerParams&, SkScalar scaleAdjust[2]);

// TODO: Move SkImageInfo2GrPixelConfig to SkGrPriv.h (requires cleanup to SkWindow its subclasses).
GrPixelConfig SkImageInfo2GrPixelConfig(const SkImageInfo& info, const GrCaps& caps);

GrSamplerParams::FilterMode GrSkFilterQualityToGrFilterMode(SkFilterQuality paintFilterQuality,
                                                            const SkMatrix& viewM,
                                                            const SkMatrix& localM,
                                                            bool* doBicubic);

#endif