总的变换矩阵:
mvpMatrix = projectionMatrix * viewMatrix * modelMatrix;
投影矩阵(projectrionMatrix):
//根据屏幕宽高计算
float ratio = (float) width / height;
//计算投影矩阵
Matrix.frustumM(mProjectionMatrix, 0, -ratio, ratio, -1, 1, 3, 7);
视图矩阵(viewMatrix):
float[] resultTransform = new float[16];
//设置观察视角 eye相机坐标 center 目标坐标 up 相机正上方 向量vuv(相机头部指向)
Matrix.setLookAtM(mViewMatrix, 0,
0, 0, 3,
0f, 0f, 0f,
0f, 1f, 0.0f);
模型矩阵(modelMatrix):
modelMatrix=translateMatrix * scaleMatrix * rotateMatrix
private final float[] mBaseMatrix = new float[]{
1f, 0f, 0f, 0f,
0f, 1f, 0f, 0f,
0f, 0f, 1f, 0f,
0f, 0f, 0f, 1f
};
// x y z 向量设置绕着哪个轴旋转
Matrix.setRotateM(mRotationMatrix, 0, mAngle, 0f, 0, 1f);
// x y z 代表缩放到比例
Matrix.scaleM(mScaleMatrix,0,mBaseMatrix,0,1f,1f,1f);
//x y z 代表位移量
Matrix.translateM(mTranslateMatrix,0,mBaseMatrix,0,0.5f,0.5f,0.0f);
使用如下函数使得2个矩阵合并:
Matrix.multiplyMM(mMVPMatrix, 0, mProjectionMatrix, 0, mViewMatrix, 0);
顶点着色器:
#version 300 es
//变换矩阵 统一变量
uniform mat4 uMVPMatrix;
//顶点
layout (location = 0) in vec4 vPosition;
//纹理坐标
layout (location = 1) in vec2 aTextureCoord;
//输出纹理坐标(s,t)
out vec2 vTexCoord;
void main() {
gl_Position = uMVPMatrix * vPosition;
vTexCoord = aTextureCoord;
}
片段着色器:
#version 300 es
//声明精度
precision mediump float;
//纹理采样器 对应一个纹理单元
uniform sampler2D texture0;
uniform sampler2D texture1;
//接收刚才顶点着色器传入的纹理坐标(s,t)
in vec2 vTexCoord;
out vec4 vFragColor;
void main() {
vFragColor = mix(texture(texture0,vTexCoord),texture(texture1,vTexCoord),0.5f);
}