Home | History | Annotate | Download | only in samplecode 
      1 /*
      2  * Copyright 2014 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 
     10 #include "Resources.h"
     11 #include "SampleCode.h"
     12 #include "SkBlurMaskFilter.h"
     13 #include "SkCanvas.h"
     14 #include "SkColorPriv.h"
     15 #include "SkImageDecoder.h"
     16 #include "SkRandom.h"
     17 #include "SkStream.h"
     18 
     19 // Intended to exercise pixel snapping observed with scaled images (and
     20 // with non-scaled images, but for a different reason):  Bug 1145
     21 
     22 class SubpixelTranslateView : public SampleView {
     23 public:
     24     SubpixelTranslateView(const char imageFilename[],
     25                           float horizontalVelocity,
     26                           float verticalVelocity)
     27       : fFilename(imageFilename),
     28         fHorizontalVelocity(horizontalVelocity),
     29         fVerticalVelocity(verticalVelocity) {
     30       SkString resourcePath = GetResourcePath();
     31       resourcePath.append("/");
     32       resourcePath.append(fFilename);
     33 
     34       SkImageDecoder* codec = NULL;
     35       SkFILEStream stream(resourcePath.c_str());
     36       if (stream.isValid()) {
     37           codec = SkImageDecoder::Factory(&stream);
     38       }
     39       if (codec) {
     40           stream.rewind();
     41           codec->decode(&stream, &fBM, kN32_SkColorType, SkImageDecoder::kDecodePixels_Mode);
     42           SkDELETE(codec);
     43       } else {
     44           fBM.allocN32Pixels(1, 1);
     45           *(fBM.getAddr32(0,0)) = 0xFF0000FF; // red == bad
     46       }
     47       fCurPos = SkPoint::Make(0,0);
     48       fSize = 200;
     49     }
     50 
     51 protected:
     52     SkBitmap fBM;
     53     SkString fFilename;
     54     SkScalar fSize;
     55     float fHorizontalVelocity, fVerticalVelocity;
     56 
     57     SkPoint fCurPos;
     58 
     59     // overrides from SkEventSink
     60     virtual bool onQuery(SkEvent* evt) SK_OVERRIDE {
     61         if (SampleCode::TitleQ(*evt)) {
     62             SampleCode::TitleR(evt, "SubpixelTranslate");
     63             return true;
     64         }
     65         return this->INHERITED::onQuery(evt);
     66     }
     67 
     68     virtual void onDrawContent(SkCanvas* canvas) SK_OVERRIDE {
     69 
     70         static const SkPaint::FilterLevel gLevels[] = {
     71             SkPaint::kNone_FilterLevel,
     72             SkPaint::kLow_FilterLevel,
     73             SkPaint::kMedium_FilterLevel,
     74             SkPaint::kHigh_FilterLevel
     75         };
     76 
     77         SkPaint paint;
     78         paint.setTextSize(48);
     79 
     80         paint.setAntiAlias(true);
     81         for (size_t i = 0; i < SK_ARRAY_COUNT(gLevels); ++i) {
     82             paint.setFilterLevel(gLevels[i]);
     83             SkRect r = SkRect::MakeXYWH( fCurPos.fX + i * (fSize + 10), fCurPos.fY, fSize, fSize );
     84             canvas->drawBitmapRect( fBM, r, &paint );
     85         }
     86 
     87         canvas->drawText( "AA Scaled", strlen("AA Scaled"), fCurPos.fX + SK_ARRAY_COUNT(gLevels) * (fSize + 10), fCurPos.fY + fSize/2, paint );
     88 
     89         paint.setAntiAlias(false);
     90         for (size_t i = 0; i < SK_ARRAY_COUNT(gLevels); ++i) {
     91             paint.setFilterLevel(gLevels[i]);
     92             SkRect r = SkRect::MakeXYWH( fCurPos.fX + i * (fSize + 10), fCurPos.fY + fSize + 10, fSize, fSize );
     93             canvas->drawBitmapRect( fBM, r, &paint );
     94         }
     95         canvas->drawText( "Scaled", strlen("Scaled"), fCurPos.fX + SK_ARRAY_COUNT(gLevels) * (fSize + 10), fCurPos.fY + fSize + 10 + fSize/2, paint );
     96 
     97         paint.setAntiAlias(true);
     98         for (size_t i = 0; i < SK_ARRAY_COUNT(gLevels); ++i) {
     99             paint.setFilterLevel(gLevels[i]);
    100             canvas->drawBitmap( fBM, fCurPos.fX + i * (fBM.width() + 10), fCurPos.fY + 2*(fSize + 10), &paint );
    101         }
    102 
    103         canvas->drawText( "AA No Scale", strlen("AA No Scale"), fCurPos.fX + SK_ARRAY_COUNT(gLevels) * (fBM.width() + 10), fCurPos.fY + 2*(fSize + 10) + fSize/2, paint );
    104 
    105         paint.setAntiAlias(false);
    106         for (size_t i = 0; i < SK_ARRAY_COUNT(gLevels); ++i) {
    107             paint.setFilterLevel(gLevels[i]);
    108             canvas->drawBitmap( fBM, fCurPos.fX + i * (fBM.width() + 10), fCurPos.fY + 2*(fSize + 10) + fBM.height() + 10, &paint );
    109         }
    110 
    111         canvas->drawText( "No Scale", strlen("No Scale"), fCurPos.fX + SK_ARRAY_COUNT(gLevels) * (fBM.width() + 10), fCurPos.fY + 2*(fSize + 10) + fBM.height() + 10 + fSize/2, paint );
    112 
    113 
    114         fCurPos.fX += fHorizontalVelocity;
    115         fCurPos.fY += fVerticalVelocity;
    116         this->inval(NULL);
    117     }
    118 
    119 private:
    120     typedef SampleView INHERITED;
    121 };
    122 
    123 //////////////////////////////////////////////////////////////////////////////
    124 
    125 static SkView* MyFactory() { return new SubpixelTranslateView("mandrill_256.png", .05f, .05f); }
    126 static SkViewRegister reg(MyFactory);
    127