blocks|key|1092611|text|我希望下面的代码序列能对您有所帮助：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1092612|Bitmap+targetBitmap+=+Bitmap.createBitmap(targetWidth,+targetHeight,+config);
Canvas+canvas+=+new+Canvas(targetBitmap);
Matrix+matrix+=+new+Matrix();
matrix.setRotate(mRotation,source.getWidth()/2,source.getHeight()/2);
canvas.drawBitmap(source,+matrix,+new+Paint());|code-block|syntax|javascript|1092613|如果您从~frameworks\base\graphics\java\android\graphics\Bitmap.java检查以下方法|offset|length|style|CODE|1092614|public+static+Bitmap+createBitmap(Bitmap+source,+int+x,+int+y,+int+width,+int+height,
++++++++Matrix+m,+boolean+filter)|1092615|这将解释它对旋转和平移的作用。|1092616|entityMap^0|0|0|4|1N|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@$I|V|J|W|K|L]]|9|@]|A|$]]|$1|M|3|N|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|Y|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|R|$]]

I hope the following sequence of code will help you:

<pre><code>Bitmap targetBitmap = Bitmap.createBitmap(targetWidth, targetHeight, config);
Canvas canvas = new Canvas(targetBitmap);
Matrix matrix = new Matrix();
matrix.setRotate(mRotation,source.getWidth()/2,source.getHeight()/2);
canvas.drawBitmap(source, matrix, new Paint());
</code></pre>

If you check the following method from <code>~frameworks\base\graphics\java\android\graphics\Bitmap.java</code>

<pre><code>public static Bitmap createBitmap(Bitmap source, int x, int y, int width, int height,
 Matrix m, boolean filter)
</code></pre>

this would explain what it does with rotation and translate.

blocks|key|877937|text|您还可以使用RotateAnimation旋转ImageView|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|877938|RotateAnimation+rotateAnimation+=+new+RotateAnimation(from,+to,
Animation.RELATIVE_TO_SELF,+0.5f,+Animation.RELATIVE_TO_SELF,
++++++++++++++++0.5f);
rotateAnimation.setInterpolator(new+LinearInterpolator());
rotateAnimation.setDuration(ANIMATION_DURATION);
rotateAnimation.setFillAfter(true);

imageView.startAnimation(rotateAnimation);|code-block|syntax|javascript|877939|entityMap^0|6|F|N|9|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

You can also rotate the <code>ImageView</code> using a <code>RotateAnimation</code>:

<pre><code>RotateAnimation rotateAnimation = new RotateAnimation(from, to,
Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
 0.5f);
rotateAnimation.setInterpolator(new LinearInterpolator());
rotateAnimation.setDuration(ANIMATION_DURATION);
rotateAnimation.setFillAfter(true);

imageView.startAnimation(rotateAnimation);
</code></pre>

blocks|key|877957|text|您可以使用类似以下内容：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|877958|Matrix+matrix+=+new+Matrix();
matrix.setRotate(mRotation,source.getWidth()/2,source.getHeight()/2);
RectF+rectF+=+new+RectF(0,+0,+source.getWidth(),+source.getHeight());
matrix.mapRect(rectF);
Bitmap+targetBitmap+=+Bitmap.createBitmap(rectF.width(),+rectF.height(),+config);
Canvas+canvas+=+new+Canvas(targetBitmap);
canvas.drawBitmap(source,+matrix,+new+Paint());|code-block|syntax|javascript|877959|​|877960|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

You can use something like following:
<pre><code>
Matrix matrix = new Matrix();
matrix.setRotate(mRotation,source.getWidth()/2,source.getHeight()/2);
RectF rectF = new RectF(0, 0, source.getWidth(), source.getHeight());
matrix.mapRect(rectF);
Bitmap targetBitmap = Bitmap.createBitmap(rectF.width(), rectF.height(), config);
Canvas canvas = new Canvas(targetBitmap);
canvas.drawBitmap(source, matrix, new Paint());
</pre></code>

blocks|key|1092717|text|看看来自谷歌的名为Lunar+Lander的样本，那里的船舶图像是动态旋转的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1092718|Lunar+Lander+code+sample|offset|length|1092719|entityMap|0|LINK|mutability|MUTABLE|url|http://developer.android.com/resources/samples/LunarLander/index.html^0|0|0|O|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@$D|P|E|Q|1|R]]|A|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|M]]]]

Look at the sample from Google called Lunar Lander, the ship image there is rotated dynamically.

<a href="http://developer.android.com/resources/samples/LunarLander/index.html" rel="nofollow">Lunar Lander code sample</a>

blocks|key|878011|text|现在我又回到了这个问题上，因为我们已经完成了游戏，我只是想把对我有用的东西贴出来。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|878012|这是旋转矩阵的方法：|878013|this.matrix.reset();
this.matrix.setTranslate(this.floatXpos,+this.floatYpos);
this.matrix.postRotate((float)this.direction,+this.getCenterX(),+this.getCenterY());+|code-block|syntax|javascript|878014|(this.getCenterX()基本上是位图X位置%2B位图宽度/+2)|offset|length|style|CODE|878015|以及用于绘制位图的方法(通过RenderManager类调用)：|878016|canvas.drawBitmap(this.bitmap,+this.matrix,+null);|878017|所以它很简单，但我发现奇怪的是，我不能让它在setRotate和postTranslate的后面工作。也许有些人知道为什么这不起作用？现在，所有位图都可以正常旋转，但位图质量并不是没有一些细微的下降:/|878018|无论如何，谢谢你的帮助！|878019|entityMap^0|0|0|0|1|H|0|E|D|0|0|1E|0|M|9|W|D|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Z|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|10|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|11|8|@$K|12|L|13|M|N]]|9|@]|A|$]]|$1|O|3|P|5|6|7|14|8|@$K|15|L|16|M|N]]|9|@]|A|$]]|$1|Q|3|R|5|6|7|17|8|@$K|18|L|19|M|N]]|9|@]|A|$]]|$1|S|3|T|5|6|7|1A|8|@$K|1B|L|1C|M|N]|$K|1D|L|1E|M|N]]|9|@]|A|$]]|$1|U|3|V|5|6|7|1F|8|@]|9|@]|A|$]]|$1|W|3|-4|5|6|7|1G|8|@]|9|@]|A|$]]]|X|$]]

I came back to this problem now that we are finalizing the game and I just thought to post what worked for me.

This is the method for rotating the Matrix:

<pre><code>this.matrix.reset();
this.matrix.setTranslate(this.floatXpos, this.floatYpos);
this.matrix.postRotate((float)this.direction, this.getCenterX(), this.getCenterY()); 
</code></pre>

(<code>this.getCenterX()</code> is basically the bitmaps X position + the bitmaps width / 2)

And the method for Drawing the bitmap (called via a <code>RenderManager</code> Class):

<code>canvas.drawBitmap(this.bitmap, this.matrix, null);</code>

So it is prettey straight forward but I find it abit strange that I couldn't get it to work by <code>setRotate</code> followed by <code>postTranslate</code>. Maybe some knows why this doesn't work? Now all the bitmaps rotate properly but it is not without some minor decrease in bitmap quality :/

Anyways, thanks for your help!

blocks|key|878041|text|我使用了这种配置，但仍然存在像素化的问题：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|878042|Bitmap+bmpOriginal+=+BitmapFactory.decodeResource(this.getResources(),+R.drawable.map_pin);
++++++++Bitmap+targetBitmap+=+Bitmap.createBitmap((bmpOriginal.getWidth()),
++++++++++++++++(bmpOriginal.getHeight()),+
++++++++++++++++Bitmap.Config.ARGB_8888);
++++++++Paint+p+=+new+Paint();
++++++++p.setAntiAlias(true);

++++++++Matrix+matrix+=+new+Matrix();+++++++
++++++++matrix.setRotate((float)+lock.getDirection(),(float)+(bmpOriginal.getWidth()/2),
++++++++++++++++(float)(bmpOriginal.getHeight()/2));

++++++++RectF+rectF+=+new+RectF(0,+0,+bmpOriginal.getWidth(),+bmpOriginal.getHeight());
++++++++matrix.mapRect(rectF);

++++++++targetBitmap+=+Bitmap.createBitmap((int)rectF.width(),+(int)rectF.height(),+Bitmap.Config.ARGB_8888);


++++++++Canvas+tempCanvas+=+new+Canvas(targetBitmap);+
++++++++tempCanvas.drawBitmap(bmpOriginal,+matrix,+p);|code-block|syntax|javascript|878043|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I used this configurations and still have the problem of pixelization :

<pre><code>Bitmap bmpOriginal = BitmapFactory.decodeResource(this.getResources(), R.drawable.map_pin);
 Bitmap targetBitmap = Bitmap.createBitmap((bmpOriginal.getWidth()),
 (bmpOriginal.getHeight()), 
 Bitmap.Config.ARGB_8888);
 Paint p = new Paint();
 p.setAntiAlias(true);

 Matrix matrix = new Matrix(); 
 matrix.setRotate((float) lock.getDirection(),(float) (bmpOriginal.getWidth()/2),
 (float)(bmpOriginal.getHeight()/2));

 RectF rectF = new RectF(0, 0, bmpOriginal.getWidth(), bmpOriginal.getHeight());
 matrix.mapRect(rectF);

 targetBitmap = Bitmap.createBitmap((int)rectF.width(), (int)rectF.height(), Bitmap.Config.ARGB_8888);


 Canvas tempCanvas = new Canvas(targetBitmap); 
 tempCanvas.drawBitmap(bmpOriginal, matrix, p);
</code></pre>

blocks|key|878049|text|matrix.reset();
matrix.setTranslate(+anchor.x,+anchor.y+);
matrix.postRotate((float)+rotation+,+0,0);
matrix.postTranslate(positionOfAnchor.x,+positionOfAnchor.x);
c.drawBitmap(bitmap,+matrix,+null);+|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|878050|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>matrix.reset();
matrix.setTranslate( anchor.x, anchor.y );
matrix.postRotate((float) rotation , 0,0);
matrix.postTranslate(positionOfAnchor.x, positionOfAnchor.x);
c.drawBitmap(bitmap, matrix, null); 
</code></pre>

I've been looking for over a day for a solution to this problem but nothing helps, even the answers here. Documentation doesn't explain anything too.

I am simply trying to get a rotation in the direction of another object. The problem is that the bitmap is not rotated around a fixed point, but rather around the bitmaps (0,0).

Here is the code I am having troubles with:

<pre><code> Matrix mtx = new Matrix();
 mtx.reset();
 mtx.preTranslate(-centerX, -centerY);
 mtx.setRotate((float)direction, -centerX, -centerY);
 mtx.postTranslate(pivotX, pivotY);
 Bitmap rotatedBMP = Bitmap.createBitmap(bitmap, 0, 0, spriteWidth, spriteHeight, mtx, true);
 this.bitmap = rotatedBMP;
</code></pre>

The weird part is, it doesn't matter how I change the values within <code>pre</code>/<code>postTranslate()</code> and the float arguments in <code>setRotation()</code>. Can someone please help and push me in the right direction? :)

Android: How to rotate a bitmap on a center point

我已经寻找了一天多的时间来解决这个问题，但是没有任何帮助，甚至这里的答案也没有。文档也没有解释任何东西。我只是想在另一个物体的方向上旋转一下。问题是位图不是围绕固定点旋转的，而是围绕位图(0,0)旋转的。下面是我遇到问题的代码：  Matrix mtx = new Matrix();  mtx.reset();  mt...

问Android:如何在中心点上旋转位图
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