底盘电池 3D 投影效果

gistfile1.txt

package com.skywell.car.myapplication.tanklevel;

import android.content.Context;
import android.graphics.Camera;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.view.View;

import androidx.annotation.Nullable;

public class BatteryView extends View {

    Paint mPaint;

    Camera camera = new Camera();
    Matrix matrix = new Matrix();

    public BatteryView(Context context) {
        super(context);
        init();
    }

    public BatteryView(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public BatteryView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    public BatteryView(Context context, @Nullable AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
        init();
    }

    private void init() {
        mPaint = new Paint();
        mPaint.setColor(Color.CYAN);
        mPaint.setStyle(Paint.Style.FILL_AND_STROKE);
        mPaint.setStrokeWidth(5);
    }

    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
        super.onLayout(changed, left, top, right, bottom);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);


//        canvas.drawRect();
        int paddingH = 40;
        int paddingV = 40;
        int width = getWidth() - paddingH * 2;
        int height = getWidth() - paddingV * 2;
//        int paddingHHalf = paddingH / 2;
//        int paddingVHalf = paddingV / 2;

//        int center1X = paddingH + (getWidth() - paddingH * 2) / 2;
//        int center1Y = paddingH + (getHeight() - paddingV * 2) / 2;
        int center1X = paddingH + width / 2;
        int center1Y = paddingV + height / 2;
        int center2X = 10 + getWidth() / 2;
        int center2Y = 10 + getHeight() / 2;


        mPaint.setColor(Color.BLUE);
        mPaint.setAlpha(255);

        canvas.drawRoundRect(paddingH, paddingV, getWidth() - paddingH, getHeight() - paddingV, 20, 20, mPaint);


        mPaint.setColor(Color.CYAN);
        mPaint.setAlpha(128);

        camera.save();
        matrix.reset();
        camera.rotateX(30);
        camera.getMatrix(matrix);
        camera.restore();
        matrix.preTranslate(-center1X, -center1Y);
        matrix.postTranslate(center1X, center1Y);
        canvas.save();
        canvas.concat(matrix);
        canvas.drawRoundRect(paddingH, paddingV, getWidth() - paddingH, getHeight() - paddingV, 10, 10, mPaint);
        canvas.restore();

//
//        camera.save();
//        matrix.reset();
//        camera.rotateY(30);
//        camera.getMatrix(matrix);
//        camera.restore();
//        matrix.preTranslate(-center2X, -center2Y);
//        matrix.postTranslate(center2X, center2Y);
//        canvas.save();
//        canvas.concat(matrix);
//        canvas.drawRect(0, 0, getWidth(), getHeight(), mPaint);
//        canvas.restore();
    }
}