gm/imagemagnifier.cpp

   1 /*
   2  * Copyright 2012 Google Inc.
   3  *
   4  * Use of this source code is governed by a BSD-style license that can be
   5  * found in the LICENSE file.
   6  */
   7
   8 #include "gm.h"
   9 #include "sk_tool_utils.h"
  10 #include "SkImageSource.h"
  11 #include "SkMagnifierImageFilter.h"
  12 #include "SkPixelRef.h"
  13 #include "SkRandom.h"
  14 #include "SkSurface.h"
  15
  16 #define WIDTH 500
  17 #define HEIGHT 500
  18
  19 DEF_SIMPLE_GM_BG(imagemagnifier, canvas, WIDTH, HEIGHT, SK_ColorBLACK) {
  20         SkPaint filterPaint;
  21         filterPaint.setImageFilter(
  22             SkMagnifierImageFilter::Make(
  23                 SkRect::MakeXYWH(SkIntToScalar(100), SkIntToScalar(100),
  24                                  SkIntToScalar(WIDTH / 2),
  25                                  SkIntToScalar(HEIGHT / 2)),
  26                 100, nullptr));
  27         canvas->saveLayer(nullptr, &filterPaint);
  28         const char* str = "The quick brown fox jumped over the lazy dog.";
  29         SkRandom rand;
  30         for (int i = 0; i < 25; ++i) {
  31             int x = rand.nextULessThan(WIDTH);
  32             int y = rand.nextULessThan(HEIGHT);
  33             SkPaint paint;
  34             sk_tool_utils::set_portable_typeface(&paint);
  35             paint.setColor(sk_tool_utils::color_to_565(rand.nextBits(24) | 0xFF000000));
  36             paint.setTextSize(rand.nextRangeScalar(0, 300));
  37             paint.setAntiAlias(true);
  38             canvas->drawString(str, SkIntToScalar(x),
  39                              SkIntToScalar(y), paint);
  40         }
  41         canvas->restore();
  42 }
  43
  44 ////////////////////////////////////////////////////////////////////////////////
  45 #define WIDTH_HEIGHT 256
  46
  47 static sk_sp<SkImage> make_img() {
  48     SkBitmap bitmap;
  49     bitmap.allocN32Pixels(WIDTH_HEIGHT, WIDTH_HEIGHT);
  50     SkCanvas canvas(bitmap);
  51
  52     canvas.clear(0x0);
  53
  54     SkPaint paint;
  55     paint.setColor(SK_ColorBLUE);
  56
  57     for (float pos = 0; pos < WIDTH_HEIGHT; pos += 16) {
  58         canvas.drawLine(0, pos, SkIntToScalar(WIDTH_HEIGHT), pos, paint);
  59         canvas.drawLine(pos, 0, pos, SkIntToScalar(WIDTH_HEIGHT), paint);
  60     }
  61
  62     SkBitmap result;
  63     result.setInfo(SkImageInfo::MakeS32(WIDTH_HEIGHT, WIDTH_HEIGHT, kPremul_SkAlphaType));
  64     result.setPixelRef(sk_ref_sp(bitmap.pixelRef()), 0, 0);
  65
  66     return SkImage::MakeFromBitmap(result);
  67 }
  68
  69 DEF_SIMPLE_GM_BG(imagemagnifier_cropped, canvas, WIDTH_HEIGHT, WIDTH_HEIGHT, SK_ColorBLACK) {
  70
  71     sk_sp<SkImage> image(make_img());
  72
  73     sk_sp<SkImageFilter> imageSource(SkImageSource::Make(std::move(image)));
  74
  75     SkRect srcRect = SkRect::MakeWH(SkIntToScalar(WIDTH_HEIGHT-32),
  76                                     SkIntToScalar(WIDTH_HEIGHT-32));
  77     srcRect.inset(64.0f, 64.0f);
  78
  79     constexpr SkScalar kInset = 64.0f;
  80
  81     // Crop out a 16 pixel ring around the result
  82     const SkRect rect = SkRect::MakeXYWH(16, 16, WIDTH_HEIGHT-32, WIDTH_HEIGHT-32);
  83     SkImageFilter::CropRect cropRect(rect);
  84
  85     SkPaint filterPaint;
  86     filterPaint.setImageFilter(SkMagnifierImageFilter::Make(srcRect, kInset,
  87                                                             std::move(imageSource),
  88                                                             &cropRect));
  89
  90     canvas->saveLayer(nullptr, &filterPaint);
  91     canvas->restore();
  92 }