[Java] [OpenGL ES3.2] Camera2.0

Camera.java

package com.Diamond.gl07;

import android.opengl.Matrix;
import android.renderscript.Matrix4f;
import android.renderscript.Float3;

public class Camera {
	private Float3 mPosition;
	private Float3 mCenter;
	private Float3 mUp;
	private Matrix4f mProjection;
    private float mYaw;
    private float mPitch;
    private float mRoll;
    private float mFovy;
    private float mAspect;
    private float mNear;
    private float mFar;
    
    
    
    public final static Float3 XY = new Float3(1,1,0);
    public final static Float3 XZ = new Float3(1,0,1);
    public final static Float3 YZ = new Float3(0,1,1);
    
    
    
	public Camera(Float3 position,Float3 center,Float3 up) {
		mPosition = position;
		mCenter = center;
		mUp = up;
		mProjection = new Matrix4f();
        mYaw = 0;
        mPitch = 0;
        mRoll = 0;
        mFovy = 120;
        mAspect = 1;
        mNear = 1;
        mFar = 100;
	}
	
	public Camera setPosition(Float3 position) {
		mPosition = position;
		return this;
	}
	public Float3 getPosition() {
		return mPosition;
	}
	
	public Camera move(Float3 distance) {
		mPosition.x += distance.x;
		mPosition.y += distance.y;
		mPosition.z += distance.z;
		return this;
	}
	
	public Camera moveX(float distance) {
		mPosition.x += distance;
		return this;
	}
    public Camera setX(float x) {
        mPosition.x = x;
        return this;
    }
	
	public Camera moveY(float distance) {
		mPosition.y += distance;
		return this;
	}
    public Camera setY(float y) {
        mPosition.y = y;
        return this;
    }
	
	public Camera moveZ(float distance) {
		mPosition.z += distance;
		return this;
	}
    public Camera setZ(float z) {
        mPosition.z = z;
        return this;
    }
	
	public Camera setCenter(Float3 center) {
		mCenter = center;
		return this;
	}
	
	public Camera setUp(Float3 up) {
		mUp = up;
		return this;
	}
	
	public Camera setPerspective(float fovy,float aspect,float near,float far) {
        mFovy = fovy;
        mAspect = aspect;
        mNear = near;
        mFar = far;
		updatePerspective();
		return this;
	}
    public Camera updatePerspective() {
        mProjection.loadIdentity();
        mProjection.loadPerspective(mFovy,mAspect,mNear,mFar);
        return this;
    }
    
    public Camera setFovy(float fovy) {
        mFovy = fovy;
        updatePerspective();
        return this;
    }
    public float getFovy() {
        return mFovy;
    }
    public Camera fovy(float angle) {
        mFovy += angle;
        updatePerspective();
        return this;
    }
    public Camera setAspect(float aspect) {
        mAspect = aspect;
        updatePerspective();
        return this;
    }
    public float getAspect() {
        return mAspect;
    }
    public Camera setNear(float near) {
        mNear = near;
        updatePerspective();
        return this;
    }
    public float getNear() {
        return mNear;
    }
    public Camera setFar(float far) {
        mFar = far;
        updatePerspective();
        return this;
    }
    public float getFar() {
        return mFar;
    }
	
	public Camera setOrtho(float l,float r,float b,float t,float n,float f) {
		mProjection.loadOrtho(l,r,b,t,n,f);
		return this;
	}
	
	public float[] getProjectionMatrix() {
		return mProjection.getArray();
	}
	
	public float[] getViewMatrix() {
		float[] view = new float[16];
		Matrix.setLookAtM(
						view,0,
						mPosition.x,mPosition.y,mPosition.z,
						mCenter.x,mCenter.y,mCenter.z,
						mUp.x,mUp.y,mUp.z
						);
		return view;
	}
    
    
    
    //这个函数有问题，明明和LearnOpenGL的一样，但是就是有问题
    public Camera updatePose() {
        if(mYaw >= 360) {
            mYaw -= 360;
        } else if(mYaw < 0) {
            mYaw += 360;
        }
        
        if(mPitch >= 90) {
            mPitch = 89.9f;
        } else if(mPitch <= -90) {
            mPitch = -89.9f;
        }
        
        if(mRoll >= 360) {
            mRoll -= 360;
        } else if(mRoll < 0) {
            mRoll += 360;
        }
        
        float x = (float)Math.cos(Math.toRadians(mYaw)) * (float)Math.cos(Math.toRadians(mPitch));
        float y = (float)Math.sin(Math.toRadians(mPitch));
        float z = (float)Math.sin(Math.toRadians(mYaw)) * (float)Math.cos(Math.toRadians(mPitch));
        
        //标准化，相当于normalize()
        float mod = (float)Math.sqrt(x * x + y * y + z * z);
        x /= mod;
        y /= mod;
        z /= mod;
        mCenter = new Float3(x,y,z);
        
        //roll的计算其实有问题，默认是朝向Z轴负半轴的
        float rx = (float)Math.sin(Math.toRadians(mRoll));
        float ry = (float)Math.cos(Math.toRadians(mRoll));
        mUp = new Float3(rx,ry,0);
        return this;
    }
    
    public Camera setOrbit(Float3 plane,float angle,float distance) {
        float x = (float)Math.sin(Math.toRadians(angle)) * distance;
        float y = (float)Math.cos(Math.toRadians(angle)) * distance;
        boolean isFirst = true;
        if(plane.x == 1) {
            mPosition.x = x;
            isFirst = false;
        }
        if(plane.y == 1) {
            if(isFirst) {
                mPosition.y = x;
                mPosition.z = y;
            } else {
                mPosition.y = y;
            }
        }
        if(plane.z == 1) {
            mPosition.z = y;
        }
        return this;
    }
    
    public Camera setYaw(float yaw) {
        mYaw = yaw;
        updatePose();
        return this;
    }
    public float getYaw() {
        return mYaw;
    }
    public Camera yaw(float angle) {
        mYaw += angle;
        updatePose();
        return this;
    }
    
    public Camera setPitch(float pitch) {
        mPitch = pitch;
        updatePose();
        return this;
    }
    public float getPitch() {
        return mPitch;
    }
    public Camera pitch(float angle) {
        mPitch += angle;
        updatePose();
        return this;
    }
    
    public Camera setRoll(float roll) {
        mRoll = roll;
        updatePose();
        return this;
    }
    public float getRoll() {
        return mRoll;
    }
    public Camera roll(float angle) {
        mRoll += angle;
        updatePose();
        return this;
    }
}

增加了缩放（通过调整fovy）和环绕（绕着一个点让摄像机环绕）
分别对应setFovy(float),fovy(float)以及setOrbit(Float3,float,float)函数

在看setOrbit()之前建议先了解三角函数和[Java] [OpenGL ES3.2] 正多边形，其实是差不多的