C++ SkColorTable::setFlags方法代码示例

// copyTo() should preserve isOpaque when it makes sense
static void test_isOpaque(skiatest::Reporter* reporter, const SkBitmap& src,
                          SkBitmap::Config dstConfig) {
    SkBitmap bitmap(src);
    SkBitmap dst;

    // we need the lock so that we get a valid colorTable (when available)
    SkAutoLockPixels alp(bitmap);
    SkColorTable* ctable = bitmap.getColorTable();
    unsigned ctableFlags = ctable ? ctable->getFlags() : 0;

    if (canHaveAlpha(bitmap.config()) && canHaveAlpha(dstConfig)) {
        bitmap.setIsOpaque(false);
        if (ctable) {
            ctable->setFlags(ctableFlags & ~SkColorTable::kColorsAreOpaque_Flag);
        }
        REPORTER_ASSERT(reporter, bitmap.copyTo(&dst, dstConfig));
        REPORTER_ASSERT(reporter, dst.config() == dstConfig);
        if (bitmap.isOpaque() != dst.isOpaque()) {
            report_opaqueness(reporter, bitmap, dst);
        }
    }

    bitmap.setIsOpaque(true);
    if (ctable) {
        ctable->setFlags(ctableFlags | SkColorTable::kColorsAreOpaque_Flag);
    }
    REPORTER_ASSERT(reporter, bitmap.copyTo(&dst, dstConfig));
    REPORTER_ASSERT(reporter, dst.config() == dstConfig);
    if (bitmap.isOpaque() != dst.isOpaque()) {
        report_opaqueness(reporter, bitmap, dst);
    }

    if (ctable) {
        ctable->setFlags(ctableFlags);
    }
}

    void drawBG(SkCanvas* canvas)
    {
        canvas->drawColor(0xFFDDDDDD);
        return;

#if 0
        SkColorTable    ct;
        SkPMColor       colors[] = { SK_ColorRED, SK_ColorBLUE };
        ct.setColors(colors, 2);
        ct.setFlags(ct.getFlags() | SkColorTable::kColorsAreOpaque_Flag);

        SkBitmap        bm;
        bm.setConfig(SkBitmap::kIndex8_Config, 20, 20, 21);
        bm.setColorTable(&ct);
        bm.allocPixels();
        sk_memset16((uint16_t*)bm.getAddr8(0, 0), 0x0001, bm.rowBytes() * bm.height() / 2);
#endif
#if 0
        SkBitmap        bm;
        bm.setConfig(SkBitmap::kRGB_565_Config, 20, 20, 42);
        bm.allocPixels();
        sk_memset32((uint32_t*)bm.getAddr16(0, 0), 0x0000FFFF, bm.rowBytes() * bm.height() / 4);
#endif
#if 1
        SkBitmap        bm;
        bm.setConfig(SkBitmap::kARGB_8888_Config, 20, 20);
        bm.allocPixels();
        sk_memset32((uint32_t*)bm.getAddr32(0, 0), 0xFFDDDDDD, bm.rowBytes() * bm.height() / 4);
#endif

        SkPaint paint;

//        SkShader* shader = SkShader::CreateBitmapShader(bm, false, SkPaint::kBilinear_FilterType, SkShader::kRepeat_TileMode);
        SkPoint pts[] = { 0, 0, SkIntToScalar(100), SkIntToScalar(0) };
        SkColor colors[] = { SK_ColorBLACK, SK_ColorWHITE };
        SkShader* shader = SkGradientShader::CreateLinear(pts, colors, NULL, 2, SkShader::kMirror_TileMode);
        paint.setShader(shader)->unref();

        canvas->drawPaint(paint);
    }

//.........这里部分代码省略.........
    }

    // we track if we actually see a non-opaque pixels, since sometimes a PNG sets its colortype
    // to |= PNG_COLOR_MASK_ALPHA, but all of its pixels are in fact opaque. We care, since we
    // draw lots faster if we can flag the bitmap has being opaque
    bool reallyHasAlpha = false;

    SkColorTable* colorTable = NULL;

    if (color_type == PNG_COLOR_TYPE_PALETTE) {
        int num_palette;
        png_colorp palette;
        png_bytep trans;
        int num_trans;

        png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette);
        
        /*  BUGGY IMAGE WORKAROUND
            
            We hit some images (e.g. fruit_.png) who contain bytes that are == colortable_count
            which is a problem since we use the byte as an index. To work around this we grow
            the colortable by 1 (if its < 256) and duplicate the last color into that slot.
        */
        int colorCount = num_palette + (num_palette < 256);

        colorTable = SkNEW_ARGS(SkColorTable, (colorCount));

        SkPMColor* colorPtr = colorTable->lockColors();
        if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
            png_get_tRNS(png_ptr, info_ptr, &trans, &num_trans, NULL);
            hasAlpha = (num_trans > 0);
        } else {
            num_trans = 0;
            colorTable->setFlags(colorTable->getFlags() | SkColorTable::kColorsAreOpaque_Flag);
        }        
        // check for bad images that might make us crash
        if (num_trans > num_palette) {
            num_trans = num_palette;
        }

        int index = 0;
        int transLessThanFF = 0;

        for (; index < num_trans; index++) {
            transLessThanFF |= (int)*trans - 0xFF;
            *colorPtr++ = SkPreMultiplyARGB(*trans++, palette->red, palette->green, palette->blue);
            palette++;
        }
        reallyHasAlpha |= (transLessThanFF < 0);

        for (; index < num_palette; index++) {
            *colorPtr++ = SkPackARGB32(0xFF, palette->red, palette->green, palette->blue);
            palette++;
        }

        // see BUGGY IMAGE WORKAROUND comment above
        if (num_palette < 256) {
            *colorPtr = colorPtr[-1];
        }
        colorTable->unlockColors(true);
    }
    
    SkAutoUnref aur(colorTable);

    if (!this->allocPixelRef(decodedBitmap, colorTable)) {
        delete colorTable;