Example usage for android.graphics Canvas Canvas

Introduction

In this page you can find the example usage for android.graphics Canvas Canvas.

Prototype

public Canvas() 

Source Link

Document

Construct an empty raster canvas.

Usage

From source file:Main.java

public static Bitmap bitmapFromDrawable(Drawable drawable) {
    Bitmap bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(),
            drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888 : Bitmap.Config.RGB_565);
    Canvas canvas = new Canvas();
    canvas.setBitmap(bitmap);/*from  w ww .  j  a v a2  s .c  o m*/
    drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
    drawable.draw(canvas);
    return bitmap;
}

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From source file:Main.java

static private Bitmap smallCoverPostProc(Bitmap smallBitmap) {
    try {/*w w  w  .  j a  va  2 s  . c o m*/
        Bitmap smallBitmapPostProc = Bitmap.createBitmap(smallBitmap.getWidth(), smallBitmap.getHeight(),
                Bitmap.Config.RGB_565);
        Canvas canvas = new Canvas();
        canvas.setBitmap(smallBitmapPostProc);
        Paint paint = new Paint();
        paint.setAntiAlias(true);
        Bitmap bitmapToShade = Bitmap.createBitmap(smallBitmap, 2, 2, smallBitmap.getWidth() - 4,
                smallBitmap.getHeight() - 4);
        BitmapShader bmShader = new BitmapShader(bitmapToShade, TileMode.CLAMP, TileMode.CLAMP);
        paint.setShader(bmShader);
        canvas.drawRoundRect(new RectF(2, 2, smallBitmap.getWidth() - 2, smallBitmap.getHeight() - 2), 4, 4,
                paint);
        return smallBitmapPostProc;
    } catch (Exception e) {
        e.printStackTrace();
        return null;
    }
}

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From source file:Main.java

public static byte[] makeFontBitmap(String font, String code, int size, float[] arrayOfPos) {
    Canvas c = new Canvas();
    Paint p = new Paint();
    float density = context.getResources().getDisplayMetrics().density;
    //        Log.v(TAG, String.format("makeFontBitmap called(Java): font=%s code=%s density=%f", font, code, density));
    p.setTextSize((float) size * density);
    p.setAntiAlias(true);//from  w w  w.  j a v a 2  s. c  o m

    Rect textBounds = new Rect();
    p.getTextBounds(code, 0, code.length(), textBounds);
    //        Log.v(TAG, String.format("makeFontBitmap textBounds: %d,%d,%d,%d", textBounds.left, textBounds.top, textBounds.right, textBounds.bottom));

    Rect textBoundsAxA = new Rect();
    String axa = String.format("A%sA", code);
    p.getTextBounds(axa, 0, axa.length(), textBoundsAxA);
    Rect textBoundsAA = new Rect();
    String aa = "AA";
    p.getTextBounds(aa, 0, aa.length(), textBoundsAA);

    // cache.distDelta = Vec2(0, 0);
    arrayOfPos[0] = textBounds.left;
    arrayOfPos[1] = textBounds.top;

    // cache.srcWidth = Vec2(16, 16);
    arrayOfPos[2] = textBounds.width();
    arrayOfPos[3] = textBounds.height();

    // cache.step = 16;
    //      arrayOfPos[4] = textBounds.width() + 1;
    arrayOfPos[4] = textBoundsAxA.width() - textBoundsAA.width();

    if (textBounds.width() == 0 || textBounds.height() == 0) {
        Log.v(TAG, "makeFontBitmap: empty");
        return null;
    }

    Bitmap b = Bitmap.createBitmap(textBounds.width(), textBounds.height(), Bitmap.Config.ARGB_8888);
    c.setBitmap(b);

    Rect r = new Rect(0, 0, textBounds.width(), textBounds.height());
    //      p.setColor(Color.RED);
    p.setARGB(0, 0, 0, 0);
    c.drawRect(r, p);
    p.setARGB(255, 255, 255, 255);

    //        Log.v(TAG, "makeFontBitmap: drawText");
    c.drawText(code, -textBounds.left, -textBounds.top, p);
    //        Log.v(TAG, String.format("makeFontBitmap: w=%.2f h=%.2f", arrayOfPos[2], arrayOfPos[3]));

    ByteBuffer buf = ByteBuffer.allocate(textBounds.width() * textBounds.height() * 4);
    //        Log.v(TAG, String.format("makeFontBitmap: b.getRowBytes() %d", b.getRowBytes()));
    buf.position(0);
    b.copyPixelsToBuffer(buf);
    //        Log.v(TAG, String.format("makeFontBitmap results: capacity=%d", buf.capacity()));

    return buf.array();
}

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From source file:Main.java

public static byte[] makeFontBitmap(String font, String code, int size, float[] arrayOfPos) {
    Log.v(TAG, String.format("makeFontBitmap called(Java): font=%s code=%s", font, code));
    Canvas c = new Canvas();
    Paint p = new Paint();
    //        Log.v(TAG, "get density");
    float density = context.getResources().getDisplayMetrics().density;
    Log.v(TAG, String.format("makeFontBitmap density: %f", density));
    p.setTextSize((float) size * density);
    p.setAntiAlias(true);/*w w  w. ja va  2 s  . com*/

    Rect textBounds = new Rect();
    p.getTextBounds(code, 0, code.length(), textBounds);
    Log.v(TAG, String.format("makeFontBitmap textBounds: %d,%d,%d,%d", textBounds.left, textBounds.top,
            textBounds.right, textBounds.bottom));

    Rect textBoundsAxA = new Rect();
    String axa = String.format("A%sA", code);
    p.getTextBounds(axa, 0, axa.length(), textBoundsAxA);
    Rect textBoundsAA = new Rect();
    String aa = "AA";
    p.getTextBounds(aa, 0, aa.length(), textBoundsAA);

    // cache.distDelta = Vec2(0, 0);
    arrayOfPos[0] = textBounds.left;
    arrayOfPos[1] = textBounds.top;

    // cache.srcWidth = Vec2(16, 16);
    arrayOfPos[2] = textBounds.width();
    arrayOfPos[3] = textBounds.height();

    // cache.step = 16;
    //      arrayOfPos[4] = textBounds.width() + 1;
    arrayOfPos[4] = textBoundsAxA.width() - textBoundsAA.width();

    if (textBounds.width() == 0 || textBounds.height() == 0) {
        Log.v(TAG, "makeFontBitmap: empty");
        return null;
    }

    Bitmap b = Bitmap.createBitmap(textBounds.width(), textBounds.height(), Bitmap.Config.ARGB_8888);
    c.setBitmap(b);

    Rect r = new Rect(0, 0, textBounds.width(), textBounds.height());
    //      p.setColor(Color.RED);
    p.setARGB(0, 0, 0, 0);
    c.drawRect(r, p);
    p.setARGB(255, 255, 255, 255);

    //        Log.v(TAG, "makeFontBitmap: drawText");
    c.drawText(code, -textBounds.left, -textBounds.top, p);
    Log.v(TAG, String.format("makeFontBitmap: w=%.2f h=%.2f", arrayOfPos[2], arrayOfPos[3]));

    ByteBuffer buf = ByteBuffer.allocate(textBounds.width() * textBounds.height() * 4);
    //      ByteBuffer buf = ByteBuffer.allocate(b.getRowBytes());
    Log.v(TAG, String.format("makeFontBitmap: b.getRowBytes() %d", b.getRowBytes()));
    buf.position(0);
    b.copyPixelsToBuffer(buf);
    Log.v(TAG, String.format("makeFontBitmap results: capacity=%d", buf.capacity()));

    //      byte bytes[] = buf.array();
    //      for (int i = 0; i < size * size * 2; i++)
    //         bytes[i] = (byte)(Math.random() * 255);
    return buf.array();
}

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From source file:Main.java

/**
 * Creates a mutable bitmap from subset of source bitmap, transformed by the optional matrix.
 *//*from   w ww .j a v a  2 s.co  m*/
private static Bitmap createBitmap(Bitmap source, int x, int y, int width, int height, Matrix m) {
    // Re-implement Bitmap createBitmap() to always return a mutable bitmap.
    Canvas canvas = new Canvas();

    Bitmap bitmap;
    Paint paint;
    if ((m == null) || m.isIdentity()) {
        bitmap = Bitmap.createBitmap(width, height, source.getConfig());
        paint = null;
    } else {
        RectF rect = new RectF(0, 0, width, height);
        m.mapRect(rect);
        bitmap = Bitmap.createBitmap(Math.round(rect.width()), Math.round(rect.height()), source.getConfig());

        canvas.translate(-rect.left, -rect.top);
        canvas.concat(m);

        paint = new Paint(Paint.FILTER_BITMAP_FLAG);
        if (!m.rectStaysRect()) {
            paint.setAntiAlias(true);
        }
    }
    bitmap.setDensity(source.getDensity());
    canvas.setBitmap(bitmap);

    Rect srcBounds = new Rect(x, y, x + width, y + height);
    RectF dstBounds = new RectF(0, 0, width, height);
    canvas.drawBitmap(source, srcBounds, dstBounds, paint);
    return bitmap;
}

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From source file:Main.java

private static Bitmap createBitmap(Bitmap source, int x, int y, int width, int height, Matrix m, float offset,
        boolean clipShadow, Paint paint) {

    int scaledWidth = width;
    int scaledHeight = height;

    final Canvas canvas = new Canvas();
    canvas.translate(offset / 2.0f, offset / 2.0f);

    Bitmap bitmap;//  w  ww .j a va 2s .  c o  m

    final Rect from = new Rect(x, y, x + width, y + height);
    final RectF to = new RectF(0, 0, width, height);

    if (m == null || m.isIdentity()) {
        bitmap = Bitmap.createBitmap(scaledWidth + (int) offset,
                scaledHeight + (int) (clipShadow ? (offset / 2.0f) : offset), Bitmap.Config.ARGB_8888);
        paint = null;
    } else {
        RectF mapped = new RectF();
        m.mapRect(mapped, to);

        scaledWidth = Math.round(mapped.width());
        scaledHeight = Math.round(mapped.height());

        bitmap = Bitmap.createBitmap(scaledWidth + (int) offset,
                scaledHeight + (int) (clipShadow ? (offset / 2.0f) : offset), Bitmap.Config.ARGB_8888);
        canvas.translate(-mapped.left, -mapped.top);
        canvas.concat(m);
    }

    canvas.setBitmap(bitmap);
    canvas.drawRect(0.0f, 0.0f, width, height, paint);
    canvas.drawBitmap(source, from, to, SCALE_PAINT);

    return bitmap;
}

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From source file:Main.java

/**
 * This method calculates maximum size of both width and height of bitmap.
 * It is twice the device screen diagonal for default implementation (extra quality to zoom image).
 * Size cannot exceed max texture size./* w  ww.j  a  v  a2 s  . co  m*/
 *
 * @return - max bitmap size in pixels.
 */
@SuppressWarnings({ "SuspiciousNameCombination", "deprecation" })
public static int calculateMaxBitmapSize(@NonNull Context context) {
    WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
    Display display = wm.getDefaultDisplay();

    Point size = new Point();
    int width, height;
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR2) {
        display.getSize(size);
        width = size.x;
        height = size.y;
    } else {
        width = display.getWidth();
        height = display.getHeight();
    }

    int screenDiagonal = (int) Math.sqrt(Math.pow(width, 2) + Math.pow(height, 2));

    Canvas canvas = new Canvas();
    return Math.min(screenDiagonal * 2,
            Math.min(canvas.getMaximumBitmapWidth(), canvas.getMaximumBitmapHeight()));
}

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From source file:Main.java

/**
 * Returns a Bitmap representing the thumbnail of the specified Bitmap. The
 * size of the thumbnail is defined by the dimension
 * android.R.dimen.launcher_application_icon_size.
 * <p>//w ww.  j a v a2 s.com
 * This method is not thread-safe and should be invoked on the UI thread
 * only.
 *
 * @param bitmap  The bitmap to get a thumbnail of.
 * @param context The application's context.
 * @return A thumbnail for the specified bitmap or the bitmap itself if the
 * thumbnail could not be created.
 */
public static Bitmap createThumbnailBitmap(Bitmap bitmap, Context context) {
    int sIconWidth = -1;
    int sIconHeight = -1;
    final Resources resources = context.getResources();
    sIconWidth = sIconHeight = (int) resources.getDimension(android.R.dimen.app_icon_size);

    final Paint sPaint = new Paint();
    final Rect sBounds = new Rect();
    final Rect sOldBounds = new Rect();
    Canvas sCanvas = new Canvas();

    int width = sIconWidth;
    int height = sIconHeight;

    sCanvas.setDrawFilter(new PaintFlagsDrawFilter(Paint.DITHER_FLAG, Paint.FILTER_BITMAP_FLAG));

    final int bitmapWidth = bitmap.getWidth();
    final int bitmapHeight = bitmap.getHeight();

    if (width > 0 && height > 0) {
        if (width < bitmapWidth || height < bitmapHeight) {
            final float ratio = (float) bitmapWidth / bitmapHeight;

            if (bitmapWidth > bitmapHeight) {
                height = (int) (width / ratio);
            } else if (bitmapHeight > bitmapWidth) {
                width = (int) (height * ratio);
            }

            final Config c = (width == sIconWidth && height == sIconHeight) ? bitmap.getConfig()
                    : Config.ARGB_8888;
            final Bitmap thumb = Bitmap.createBitmap(sIconWidth, sIconHeight, c);
            final Canvas canvas = sCanvas;
            final Paint paint = sPaint;
            canvas.setBitmap(thumb);
            paint.setDither(false);
            paint.setFilterBitmap(true);
            sBounds.set((sIconWidth - width) / 2, (sIconHeight - height) / 2, width, height);
            sOldBounds.set(0, 0, bitmapWidth, bitmapHeight);
            canvas.drawBitmap(bitmap, sOldBounds, sBounds, paint);
            return thumb;
        } else if (bitmapWidth < width || bitmapHeight < height) {
            final Config c = Config.ARGB_8888;
            final Bitmap thumb = Bitmap.createBitmap(sIconWidth, sIconHeight, c);
            final Canvas canvas = sCanvas;
            final Paint paint = sPaint;
            canvas.setBitmap(thumb);
            paint.setDither(false);
            paint.setFilterBitmap(true);
            canvas.drawBitmap(bitmap, (sIconWidth - bitmapWidth) / 2, (sIconHeight - bitmapHeight) / 2, paint);
            return thumb;
        }
    }

    return bitmap;
}

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