canvas图片旋转,该如何处理

canvas图片旋转

Canvas 旋转，地球月亮
[解决办法]
你用canvas，那就应该是2D绘图了，2D的话，地球自转使用matrix就行，我给你画布旋转的方法吧，比较简单:


        Matrix m = new Matrix();
        m.postTranslate(x,y);//移动到地球中心点
        m.postRotate(degree);//旋转
        c.drawBitmap(bmp,m,paint);//画地球

月球公转的话，使用下面函数来计算圆形上某点坐标：


    protected float xn(float pointX,float pointY,float x,float y,double angle){
        double angleHude = Math.toRadians(angle);//角度转弧度
        double cosAngle = Math.cos(angleHude);
        double sinAngle = Math.sin(angleHude);
        return (float)((pointX-x)*cosAngle-(pointY-y)*sinAngle+x);
    }

    protected float yn(float pointX,float pointY,float x,float y,double angle){
        double angleHude = Math.toRadians(angle);//角度转弧度
        double cosAngle = Math.cos(angleHude);
        double sinAngle = Math.sin(angleHude);
        return (float)((pointX-x)*sinAngle+(pointY-y)*cosAngle+y);
    }

[解决办法]
那个是我没考虑周全
先给你地球自转的吧，公转的我看看下班之前能不能给你写出来：


package org.yye.android.commons.rotate;

import android.app.Activity;
import android.content.Context;
import android.graphics.*;
import android.os.Bundle;
import android.os.Handler;

import android.util.DisplayMetrics;
import android.view.WindowManager;
import android.widget.ImageView;
import org.yye.android.commons.R;

import java.util.HashMap;
import java.util.Map;

/**
 * User: ye.yang
 * Date: 13-5-10
 * Time: 上午10:57
 */
public class RotateActivity extends Activity {
    private float degree = 0f;
    private Canvas c;
    private Paint p;
    private Handler handler = new Handler();
    private ImageView iv;
    private int w,h;
    private Bitmap earthBmp; 
 
    private int earthW,earthH;
    private Runnable task = new Runnable() {
        @Override
        public void run() {
            handler.postDelayed(this,(long)(0.01*1000));
            degree++;
            //Bitmap backgroundBmp = BitmapFactory.decodeResource(getResources(),R.drawable.grid);
            Bitmap backgroundBmp = Bitmap.createBitmap(w,h, Bitmap.Config.ARGB_8888);
            c = new Canvas(backgroundBmp);
            p = new Paint(Paint.ANTI_ALIAS_FLAG 
[解决办法]
 Paint.DEV_KERN_TEXT_FLAG);

            Rect r = new Rect(w/2-earthW/2,h/2-earthH/2,w/2+earthW/2,h/2+earthH/2);

            c.save();
            c.rotate(degree, w / 2, h / 2);
            c.drawBitmap(earthBmp, null, r, p);
            c.restore();
            p.setStyle(Paint.Style.STROKE);
            c.drawRect(r,p);

            iv.setImageBitmap(backgroundBmp);
        }
    };

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.rotate);
        w=getMetrics().get("width");
        h=getMetrics().get("height");
        earthBmp = BitmapFactory.decodeResource(getResources(),R.drawable.earth);
        earthW = earthBmp.getWidth();
        earthH = earthBmp.getHeight();
        iv = (ImageView)findViewById(R.id.rotate_iv);
        handler.post(task);
    }

    private Map&lt;String, Integer&gt; getMetrics() {
        DisplayMetrics displayMetrics = new DisplayMetrics();
        WindowManager wm = getWindowManager();
        if(wm == null)
            wm = (WindowManager)getSystemService(Context.WINDOW_SERVICE);
        if (wm != null) {
            wm.getDefaultDisplay().getMetrics(displayMetrics); 
 
        }
        int height = displayMetrics.heightPixels;
        int width = displayMetrics.widthPixels;
        Map&lt;String, Integer&gt; resultMap = new HashMap&lt;String, Integer&gt;();
        resultMap.put("width", width);
        resultMap.put("height", height);
        return resultMap;
    }

    protected float xn(float pointX,float pointY,float x,float y,double angle){
        double angleHude = Math.toRadians(angle);//角度转弧度
        double cosAngle = Math.cos(angleHude);
        double sinAngle = Math.sin(angleHude);
        return (float)((pointX-x)*cosAngle-(pointY-y)*sinAngle+x);
    }

    protected float yn(float pointX,float pointY,float x,float y,double angle){
        double angleHude = Math.toRadians(angle);//角度转弧度
        double cosAngle = Math.cos(angleHude);
        double sinAngle = Math.sin(angleHude);
        return (float)((pointX-x)*sinAngle+(pointY-y)*cosAngle+y);
    }
}

[解决办法]
要下班了，先给你发一个吧，公转速度计算得有问题，中心点计算也有问题，你先看看吧。。:


package org.yye.android.commons.rotate;

import android.app.Activity;
import android.content.Context;
import android.graphics.*;
import android.os.Bundle;
import android.os.Handler;

import android.util.DisplayMetrics;
import android.view.WindowManager;
import android.widget.ImageView;
import org.yye.android.commons.R;

import java.util.HashMap;
import java.util.Map;

/**
 * User: ye.yang
 * Date: 13-5-10
 * Time: 上午10:57
 */
public class RotateActivity extends Activity {
    private float earthDegree = 0f;
    private float moonDegree = 0f;

    private Canvas c;
    private Paint p;
    private Handler handler = new Handler();
    private ImageView iv;
    private int w,h;
    private Bitmap earthBmp,moonBmp;
    private int earthW,earthH;
    private float moonX,moonY;
    private Runnable task = new Runnable() {
        @Override
        public void run() {
            handler.postDelayed(this,(long)(0.01*1000));
            earthDegree++; 
 
            Bitmap backgroundBmp = Bitmap.createBitmap(w,h, Bitmap.Config.ARGB_8888);
            c = new Canvas(backgroundBmp);
            p = new Paint(Paint.ANTI_ALIAS_FLAG 
[解决办法]
 Paint.DEV_KERN_TEXT_FLAG);

            Rect r = new Rect(w/2-earthW/2,h/2-earthH/2,w/2+earthW/2,h/2+earthH/2);

            c.save();
            c.rotate(earthDegree, w / 2, h / 2);
            c.drawBitmap(earthBmp, null, r, p);
            c.restore();
            p.setStyle(Paint.Style.STROKE);
            c.drawRect(r,p);

            moonDegree+=(1f/30);//自转一天的角度=公转30天的角度，都是360°，所以简单/30
            float tempX = moonX;
            moonX = xn(tempX,moonY,w/2,h/2, moonDegree);
            moonY = yn(tempX,moonY,w/2,h/2, moonDegree);
            c.drawBitmap(moonBmp,moonX,moonY,p);

            iv.setImageBitmap(backgroundBmp);
        }
    };

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.rotate);
        w=getMetrics().get("width");
        h=getMetrics().get("height");
        earthBmp = BitmapFactory.decodeResource(getResources(), R.drawable.earth);
        moonBmp = BitmapFactory.decodeResource(getResources(), R.drawable.moon);
        earthW = earthBmp.getWidth();
        earthH = earthBmp.getHeight();
        moonX = w/2+100;
        moonY = h/2;
        iv = (ImageView)findViewById(R.id.rotate_iv);
        handler.post(task);
    }

    private Map&lt;String, Integer&gt; getMetrics() {
        DisplayMetrics displayMetrics = new DisplayMetrics();
        WindowManager wm = getWindowManager();
        if(wm == null)
            wm = (WindowManager)getSystemService(Context.WINDOW_SERVICE); 
 
        if (wm != null) {
            wm.getDefaultDisplay().getMetrics(displayMetrics);
        }
        int height = displayMetrics.heightPixels;
        int width = displayMetrics.widthPixels;
        Map&lt;String, Integer&gt; resultMap = new HashMap&lt;String, Integer&gt;();
        resultMap.put("width", width);
        resultMap.put("height", height);
        return resultMap;
    }

    protected float xn(float pointX,float pointY,float x,float y,double angle){
        double angleHude = Math.toRadians(angle);//角度转弧度
        double cosAngle = Math.cos(angleHude);
        double sinAngle = Math.sin(angleHude);
        return (float)((pointX-x)*cosAngle-(pointY-y)*sinAngle+x);
    }

    protected float yn(float pointX,float pointY,float x,float y,double angle){
        double angleHude = Math.toRadians(angle);//角度转弧度
        double cosAngle = Math.cos(angleHude);
        double sinAngle = Math.sin(angleHude);
        return (float)((pointX-x)*sinAngle+(pointY-y)*cosAngle+y);
    }
}

[解决办法]
是否可以考虑用动画实现？
[解决办法]
http://www.eoeandroid.com/thread-653-1-1.html 看一下这个
[解决办法]
原来想太多了，其实公转也可以用同样的方法实现，这个应该是没问题了，在本机跑过了：
[code=java-android]
package org.yye.android.commons.rotate;

import android.app.Activity;
import android.content.Context;
import android.graphics.*;
import android.os.Bundle;
import android.os.Handler;

import android.util.DisplayMetrics;

import android.view.WindowManager;
import android.widget.ImageView;
import org.yye.android.commons.R;

import java.util.HashMap;
import java.util.Map;

/**
* User: ye.yang
* Date: 13-5-10
* Time: 上午10:57
*/
public class RotateActivity extends Activity {
private float earthDegree = 0f;
private float moonDegree = 0f;

private Canvas c;
private Paint p;
private Handler handler = new Handler();
private ImageView iv;
private int w,h;
private Bitmap earthBmp,moonBmp;
private int earthW,earthH;
private int moonW,moonH;

private Runnable task = new Runnable() {
@Override
public void run() {
handler.postDelayed(this,(long)(0.01*1000));
earthDegree++;
Bitmap backgroundBmp = Bitmap.createBitmap(w,h, Bitmap.Config.ARGB_8888);
c = new Canvas(backgroundBmp);
p = new Paint(Paint.ANTI_ALIAS_FLAG
[解决办法]
Paint.DEV_KERN_TEXT_FLAG);

Rect r = new Rect(w/2-earthW/2,h/2-earthH/2,w/2+earthW/2,h/2+earthH/2);

c.save();
c.rotate(earthDegree, w / 2, h / 2);
c.drawBitmap(earthBmp, null, r, p);
c.restore();
p.setStyle(Paint.Style.STROKE);
c.drawRect(r,p);

//自转一天的角度=公转30天的角度，都是360°，所以简单/30
moonDegree-=(1f/10);//除与30太慢了，就/10了
Rect rMoon = new Rect(w/2-moonW/2-50,h/2-moonH/2-50,w/2+moonW/2-50,h/2+moonH/2-50);
c.save();
c.rotate(moonDegree,w/2,h/2);
c.drawBitmap(moonBmp,null,rMoon,p);
c.restore();

iv.setImageBitmap(backgroundBmp);
}
};

public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.rotate);
w=getMetrics().get("width");
h=getMetrics().get("height");
earthBmp = BitmapFactory.decodeResource(getResources(), R.drawable.earth);
moonBmp = BitmapFactory.decodeResource(getResources(), R.drawable.moon);
earthW = earthBmp.getWidth();
earthH = earthBmp.getHeight();
moonW = moonBmp.getWidth();
moonH = moonBmp.getHeight();
iv = (ImageView)findViewById(R.id.rotate_iv);

handler.post(task);
}

private Map<String, Integer> getMetrics() {
DisplayMetrics displayMetrics = new DisplayMetrics();
WindowManager wm = getWindowManager();
if(wm == null)
wm = (WindowManager)getSystemService(Context.WINDOW_SERVICE);
if (wm != null) {
wm.getDefaultDisplay().getMetrics(displayMetrics);
}
int height = displayMetrics.heightPixels;
int width = displayMetrics.widthPixels;
Map<String, Integer> resultMap = new HashMap<String, Integer>();
resultMap.put("width", width);
resultMap.put("height", height);
return resultMap;
}
}
[/code]
[解决办法]
这个。。分呢？
[解决办法]
赶紧给分啊！

canvas图片旋转,该如何处理

热点推荐