package com.chenjim.glrecorder.filter;

import android.content.Context;
import android.opengl.GLES11Ext;
import android.opengl.GLES20;

import com.chenjim.glrecorder.R;


/**
 * 不需要显示到屏幕上
 * 写入fbo (帧缓存)
 */
public class CameraFilter extends AbstractFrameFilter {


    private float[] matrix;


    public CameraFilter(Context context) {
        super(context, R.raw.camera_vertex, R.raw.camera_frag);
    }

    @Override
    protected void initCoordinate() {
        mGLTextureBuffer.clear();
        //摄像头是颠倒的
//        float[] TEXTURE = {
//                0.0f, 0.0f,
////                1.0f, 0.0f,
////                0.0f, 1.0f,
////                1.0f, 1.0f
//        };
        //调整好了镜像
//        float[] TEXTURE = {
//                1.0f, 0.0f,
//                0.0f, 0.0f,
//                1.0f, 1.0f,
//                0.0f, 1.0f,
//        };
        //修复旋转 逆时针旋转90度
        float[] TEXTURE = {
                0.0f, 0.0f,
                0.0f, 1.0f,
                1.0f, 0.0f,
                1.0f, 1.0f,
        };
        mGLTextureBuffer.put(TEXTURE);
    }


    @Override
    public int onDrawFrame(int textureId) {
        //设置显示窗口
        GLES20.glViewport(0, 0, mOutputWidth, mOutputHeight);

        //不调用的话就是默认的操作glsurfaceview中的纹理了。显示到屏幕上了
        //这里我们还只是把它画到fbo中(缓存)
        GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, mFrameBuffers[0]);

        //使用着色器
        GLES20.glUseProgram(mGLProgramId);

        //传递坐标
        mGLVertexBuffer.position(0);
        GLES20.glVertexAttribPointer(vPosition, 2, GLES20.GL_FLOAT, false, 0, mGLVertexBuffer);
        GLES20.glEnableVertexAttribArray(vPosition);

        mGLTextureBuffer.position(0);
        GLES20.glVertexAttribPointer(vCoord, 2, GLES20.GL_FLOAT, false, 0, mGLTextureBuffer);
        GLES20.glEnableVertexAttribArray(vCoord);

        //变换矩阵
        GLES20.glUniformMatrix4fv(vMatrix, 1, false, matrix, 0);

        GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
        //因为这一层是摄像头后的第一层，所以需要使用扩展的  GL_TEXTURE_EXTERNAL_OES
        GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, textureId);
        GLES20.glUniform1i(vTexture, 0);

        GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);

        GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, 0);
        GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, 0);
        //返回fbo的纹理id
        return mFrameBufferTextures[0];
    }


    public void setMatrix(float[] matrix) {
        this.matrix = matrix;
    }
}