Can we construct a bitmap from a rect.
I draw a bitmap in a rect and want strokes drawn on the bitmap image become part of the image.
I am wondering if I can construct a bitmap from a Rect so the new bitmap has the old image and the strokes as a single image.
Thank You
You can always take a canvas to help you create an already decoded bitmap the way you want:
Bitmap originalBmp = null;//Here goes original Bitmap...
ImageView img = null;//Any imageview holder you are using...
Bitmap modifiedBmp = Bitmap.createBitmap(100, 100, Bitmap.Config.ARGB_8888);//Configure with your proper size and color
Canvas canvas = new Canvas(modifiedBmp);
//At this point the modified bitmap has the original one, starting from here, you can add any overlay you want...
canvas.drawBitmap(originalBmp, 0, 0, new Paint());
//And do all the other modifications you want here...
canvas.drawLines(new float[]{}, null);
canvas.drawCircle(x, y, radius, null);
//At this point the modified bitmap will have anything you added
img.setImageBitmap(modifiedBmp);
// IF YOU ARE OVERRIDING ONDRAW METHOD
public void onDraw(Canvas canvas){
//Here DO your DRAW BITMAP NOTE: paint must be already created...
canvas.drawBitmap(bt, 0, 0, paint);
paint.setColor(Color.BLACK);
paint.setStrokeWidth(3);
canvas.drawRect(30, 30, 80, 80, paint);
super.onDraw(canvas);
}
Regards!
Yes you can , Using canvas you can draw something on your old bimtap .
Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),
bitmap.getHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(output);
final int color = 0xff424242;
final Paint paint = new Paint();
final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
paint.setAntiAlias(true);
canvas.drawARGB(0, 0, 0, 0);
paint.setColor(color);
// do some canvas drawing
canvas.drawBitmap(bitmap, rect, rect, paint);
Related
I am drawing text on a canvas. I would like to draw a solid circle of color over the text, and only have the circle be painted where it intersects the text. Example:
and what I want to do:
I'm not sure if this is possible, my draw code is simply:
public void onDraw(Canvas canvas) {
canvas.drawText("Hello", x, y, paint);
paint.setColor(orange);
canvas.drawOval(...);
}
I suppose I would need to apply some masking, but not sure how to get started.
follow this tutorial from a googler...
android-shaders-filters
BitmapShader may help you
You can use PorterDuffXfermode in Android to achieve this.
If you use below code it will work fine:
Bitmap original = Bitmap.createBitmap(canvas.getWidth(), canvas.getHeight(),
Bitmap.Config.ARGB_8888); // Created from Canvas
Bitmap mask =
Bitmap.createBitmap(getContext().getResources(),R.drawable.mask_image);
Bitmap result = Bitmap.createBitmap(mask.getWidth(), mask.getHeight(),
Config.ARGB_8888);
Canvas tempCanvas = new Canvas(result);
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
tempCanvas.drawBitmap(original, 0, 0, null);
paint.setXfermode(new PorterDuffXfermode(Mode.DST_IN));
tempCanvas.drawBitmap(mask, 0, 0, paint);
paint.setXfermode(null);
canvas.drawBitmap(result, 0, 0, new Paint());
What does PorterDuff.Mode mean in android graphics.What does it do?
I want to be able to use the following image to mask other bitmap. So basically, I'm trying to get the mask image and replace it's black content with another bitmap. Like this for example:
I'm able to use this mask and create a round version of the original bitmap, but that does not retain that orange border around it. Any thoughts on how I can accomplish this effect? Thanks.
The code that I am using (that only creates a round image) is the following:
private static Bitmap applyMask(ImageView imageView, Bitmap mainImage) {
Canvas canvas = new Canvas();
Bitmap result result = Bitmap.createBitmap(50, 50, Bitmap.Config.ARGB_8888);
canvas.setBitmap(result);
Paint paint = new Paint();
// resize image fills the whole canvas
canvas.drawBitmap(mainImage, null, new Rect(0, 0, 50, 50), paint);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));
canvas.drawBitmap(sMaskImage, 0, 0, paint);
paint.setXfermode(null);
return result;
}
I use below code snipped to set masked images, this sample "bm" is my bitmap and "mMaskSource" is the resource id of mask object position in my drawable folder.
Bitmap mask = BitmapFactory.decodeResource(getResources(), mMaskSource);
Bitmap result = Bitmap.createBitmap(mask.getWidth(), mask.getHeight(),
Config.ARGB_8888);
Canvas mCanvas = new Canvas(result);
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));
bm = Bitmap.createScaledBitmap(bm, mask.getWidth(), mask.getHeight(),
true);
mCanvas.drawBitmap(bm, 0, 0, null);
mCanvas.drawBitmap(mask, 0, 0, paint);
paint.setXfermode(null);
And finally you can use "result" bitmap object however you wish.
Following is my program and reference picture.
Program :
int width = src.getWidth();
int height = src.getHeight();
Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas (bitmap);
Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setDither(true);
canvas.drawBitmap(src, 0, 0, paint);
paint.setXfermode(new PorterDuffXfermode(Mode.MULTIPLY));
paint.setColor(Color.RED);
paint.setAlpha(35);
canvas.drawRect(0, 0, width, height, paint);
Reference picture :
I used above program to add a light transparent red color (with alpha) to the photo. But I am not clear why the photo changed to deep deep red. The "ideal result" is made by Photoshop. I just add a red layer before the original photo. And than change to a low transparence and MULTIPLY.
Are they not the same processing concept or my program has anything wrong? Does it can't use Mode.MULTIPLY to create the "ideal result"? Can anybody give some opinion to me?
thanks thanks thanks a lot!
Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
Canvas mCanvas = new Canvas(bitmap);
Paint paint = new Paint();
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.LIGHTEN));
paint.setColor(Color.RED);
paint.setAlpha(95);
mCanvas.drawBitmap(src, 0, 0, null);
mCanvas.drawRect(0, 0, src.getWidth(), src.getHeight(), paint);
With mode Lighten and Alpha as 95 I'm getting something nearer to your requirement.
Result:
I need to crop a Bitmap, but instead of having a rectangular cropped image (which I managed successfully to do), I need it to be any form defined by coordinates.
I'm following the answer from this thread: Cutting a multipoint ploygon out of Bitmap and placing it on transparency , and trying to implement it, but unfortunatly it does not clip the image.
I did as in the description, but it seems there's a bug somewhere. The image is drawn in rectangular way.
Am I missing something?
Bitmap originalBitmap=BitmapFactory.decodeResource(getResources(), R.drawable.test_image);
// Image cropped
Bitmap croppedBitmap=Bitmap.createBitmap(originalBitmap, 10, 10, 200, 200);
Canvas canvas=new Canvas(croppedBitmap);
// Create a path
Path path=new Path();
path.setFillType(FillType.INVERSE_EVEN_ODD);
path.moveTo(0, 0);
path.moveTo(0, 100);
path.moveTo(100, 0);
path.moveTo(0, 0);
// Paint with Xfermode
Paint paint=new Paint();
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));
// Draw the path
canvas.drawPath(path, paint);
imageView.setImageBitmap(croppedBitmap);
I was very close to the solution. Here it is:
compositeImageView = (ImageView) findViewById(R.id.imageView);
Bitmap bitmap1=BitmapFactory.decodeResource(getResources(), R.drawable.batman_ad);
Bitmap bitmap2=BitmapFactory.decodeResource(getResources(), R.drawable.logo);
Bitmap resultingImage=Bitmap.createBitmap(320, 480, bitmap1.getConfig());
Canvas canvas = new Canvas(resultingImage);
Paint paint = new Paint();
paint.setAntiAlias(true);
Path path=new Path();
path.lineTo(150, 0);
path.lineTo(230, 120);
path.lineTo(70, 120);
path.lineTo(150, 0);
canvas.drawPath(path, paint);
paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
canvas.drawBitmap(bitmap2, 0, 0, paint);
compositeImageView.setImageBitmap(resultingImage);
I need to create a custom view amd in onDraw method I need to draw some bitmaps, using a mask. I created a paint:
Paint maskPaint = new Paint();
maskPaint.setAntiAlias(true);
maskPaint.setXfermode(new AvoidXfermode(Color.RED, 0, AvoidXfermode.Mode.TARGET));
and I draw my bitmap on canvas using this paint. My problem is that at the corners, my mask have some pixels with alpha less than 255. Is there a way to draw my bitmap's pixels on the mask with the same alpha that mask image has on those pixels with aplha greater than zero?
private Bitmap maskingImage(Bitmap s, int drawable) {
Bitmap original = s;
Bitmap mask = BitmapFactory.decodeResource(getResources(),drawable);
Bitmap result = Bitmap.createBitmap(mask.getWidth(), mask.getHeight(),Bitmap.Config.ARGB_8888);
Canvas mCanvas = new Canvas(result);
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));
mCanvas.drawBitmap(original, 0, 0, null);
mCanvas.drawBitmap(mask, 0, 0, paint);
paint.setXfermode(null);
return result;
}
Resources resources = this.getResources();
Bitmap mask = BitmapFactory.decodeResource(resources,R.drawable.fx_lightleak2_small);
int width=bMap.getWidth();
int height=bMap.getHeight();
Bitmap resizedbitmap=Bitmap.createScaledBitmap(mask, width, height, true);
Bitmap result = Bitmap.createBitmap(bMap.getWidth(), bMap.getHeight(), Config.ARGB_8888);
Canvas c = new Canvas(result);
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setXfermode(new PorterDuffXfermode(Mode.LIGHTEN));
c.drawBitmap(bMap, 0, 0, null);
paint.setAlpha(200);
c.drawBitmap(resizedbitmap, 0, 0, paint);
paint.setXfermode(null);
effect_5.setImageBitmap(result);