gm/swizzle.cpp

/*
 * Copyright 2019 Google LLC.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "gm/gm.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkImageInfo.h"
#include "include/core/SkMatrix.h"
#include "include/core/SkRect.h"
#include "include/core/SkTypes.h"
#include "src/core/SkCanvasPriv.h"
#include "src/gpu/GrFragmentProcessor.h"
#include "src/gpu/SkGr.h"
#include "src/gpu/SurfaceFillContext.h"
#include "src/gpu/effects/GrTextureEffect.h"
#include "tools/Resources.h"

DEF_SIMPLE_GPU_GM(swizzle, rContext, canvas, 512, 512) {
    auto sfc = SkCanvasPriv::TopDeviceSurfaceFillContext(canvas);
    if (!sfc) {
        return;
    }

    SkBitmap bmp;
    GetResourceAsBitmap("images/mandrill_512_q075.jpg", &bmp);
    auto view = std::get<0>(GrMakeCachedBitmapProxyView(rContext, bmp, GrMipmapped::kNo));
    if (!view) {
        return;
    }
    std::unique_ptr<GrFragmentProcessor> imgFP =
        GrTextureEffect::Make(std::move(view), bmp.alphaType(), SkMatrix());
    auto fp = GrFragmentProcessor::SwizzleOutput(std::move(imgFP), GrSwizzle("grb1"));

    sfc->fillWithFP(std::move(fp));
}