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      1 /*
      2  * Copyright 2013 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 "SkBitmap.h"
     10 #include "SkCanvas.h"
     11 #include "SkColor.h"
     12 #include "SkShader.h"
     13 
     14 namespace skiagm {
     15 
     16 // This GM draws a 3x3 grid (with the center element excluded) of rectangles
     17 // filled with a bitmap shader. The bitmap shader is transformed so that the
     18 // pattern cell is at the center (excluded) region.
     19 //
     20 // In Repeat and Mirror mode, this tests that the bitmap shader still draws
     21 // even though the pattern cell is outside the clip.
     22 //
     23 // In Clamp mode, this tests that the clamp is handled properly. For PDF,
     24 // (and possibly other exported formats) this also "tests" that the image itself
     25 // is not stored (well, you'll need to open it up with an external tool to
     26 // verify that).
     27 
     28 static SkBitmap create_bitmap() {
     29     SkBitmap bmp;
     30     bmp.setConfig(SkBitmap::kARGB_8888_Config, 2, 2);
     31     bmp.allocPixels();
     32     bmp.lockPixels();
     33     uint32_t* pixels = reinterpret_cast<uint32_t*>(bmp.getPixels());
     34     pixels[0] = SkPreMultiplyColor(SK_ColorRED);
     35     pixels[1] = SkPreMultiplyColor(SK_ColorGREEN);
     36     pixels[2] = SkPreMultiplyColor(SK_ColorBLACK);
     37     pixels[3] = SkPreMultiplyColor(SK_ColorBLUE);
     38     bmp.unlockPixels();
     39 
     40     return bmp;
     41 }
     42 
     43 static const SkScalar RECT_SIZE = 64;
     44 static const SkScalar SLIDE_SIZE = 300;
     45 
     46 class ClippedBitmapShadersGM : public GM {
     47 public:
     48     ClippedBitmapShadersGM(SkShader::TileMode mode, bool hq=false)
     49     : fMode(mode), fHQ(hq) {
     50     }
     51 
     52 protected:
     53     SkShader::TileMode fMode;
     54     bool fHQ;
     55 
     56     virtual SkString onShortName() {
     57         SkString descriptor;
     58         switch (fMode) {
     59             case SkShader::kRepeat_TileMode:
     60                 descriptor = "tile";
     61             break;
     62             case SkShader::kMirror_TileMode:
     63                 descriptor = "mirror";
     64             break;
     65             case SkShader::kClamp_TileMode:
     66                 descriptor = "clamp";
     67             break;
     68             default:
     69                 SkASSERT(false);
     70         }
     71         descriptor.prepend("clipped-bitmap-shaders-");
     72         if (fHQ) {
     73             descriptor.append("-hq");
     74         }
     75         return descriptor;
     76     }
     77 
     78     virtual SkISize onISize() {
     79         return SkISize::Make(300, 300);
     80     }
     81 
     82     virtual void onDraw(SkCanvas* canvas) {
     83         SkBitmap bmp = create_bitmap();
     84         SkShader* shader = SkShader::CreateBitmapShader(
     85                 bmp, fMode, fMode);
     86 
     87         SkPaint paint;
     88         SkMatrix s;
     89         s.reset();
     90         s.setScale(8, 8);
     91         s.postTranslate(SLIDE_SIZE / 2, SLIDE_SIZE / 2);
     92         shader->setLocalMatrix(s);
     93         paint.setShader(shader)->unref();
     94 
     95         if (fHQ) {
     96             paint.setFilterLevel(SkPaint::kHigh_FilterLevel);
     97         }
     98 
     99         SkScalar margin = (SLIDE_SIZE / 3 - RECT_SIZE) / 2;
    100         for (int i = 0; i < 3; i++) {
    101             SkScalar yOrigin = SLIDE_SIZE / 3 * i + margin;
    102             for (int j = 0; j < 3; j++) {
    103                 SkScalar xOrigin = SLIDE_SIZE / 3 * j + margin;
    104                 if (i == 1 && j == 1) {
    105                     continue;   // skip center element
    106                 }
    107                 SkRect rect = SkRect::MakeXYWH(xOrigin, yOrigin,
    108                                                RECT_SIZE, RECT_SIZE);
    109                 canvas->save();
    110                 canvas->clipRect(rect);
    111                 canvas->drawRect(rect, paint);
    112                 canvas->restore();
    113             }
    114         }
    115     }
    116 
    117 private:
    118     typedef GM INHERITED;
    119 };
    120 
    121 //////////////////////////////////////////////////////////////////////////////
    122 
    123 DEF_GM( return new ClippedBitmapShadersGM(SkShader::kRepeat_TileMode); )
    124 DEF_GM( return new ClippedBitmapShadersGM(SkShader::kMirror_TileMode); )
    125 DEF_GM( return new ClippedBitmapShadersGM(SkShader::kClamp_TileMode); )
    126 
    127 DEF_GM( return new ClippedBitmapShadersGM(SkShader::kRepeat_TileMode, true); )
    128 DEF_GM( return new ClippedBitmapShadersGM(SkShader::kMirror_TileMode, true); )
    129 DEF_GM( return new ClippedBitmapShadersGM(SkShader::kClamp_TileMode, true); )
    130 
    131 
    132 }
    133