1// Copyright 2019 Google LLC.
2// Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
3#include <memory>
4
5#include "tools/fiddle/examples.h"
6// HASH=4486d0c0b22ad2931db130f42da4c80c
7REG_FIDDLE(Canvas_accessTopRasterHandle, 256, 256, true, 0) {
8static void DeleteCallback(void*, void* context) {
9    delete (char*) context;
10}
11class CustomAllocator : public SkRasterHandleAllocator {
12public:
13    bool allocHandle(const SkImageInfo& info, Rec* rec) override {
14        char* context = new char[4]{'s', 'k', 'i', 'a'};
15        rec->fReleaseProc = DeleteCallback;
16        rec->fReleaseCtx = context;
17        rec->fHandle = context;
18        rec->fPixels = context;
19        rec->fRowBytes = 4;
20        return true;
21    }
22    void updateHandle(Handle handle, const SkMatrix& ctm, const SkIRect& clip_bounds) override {
23        // apply canvas matrix and clip to custom environment
24    }
25};
26
27void draw(SkCanvas* canvas) {
28    const SkImageInfo info = SkImageInfo::MakeN32Premul(1, 1);
29    std::unique_ptr<SkCanvas> c2 =
30            SkRasterHandleAllocator::MakeCanvas(std::make_unique<CustomAllocator>(), info);
31    char* context = (char*) c2->accessTopRasterHandle();
32    SkDebugf("context = %.4s\n", context);
33}
34}  // END FIDDLE
35