[실시간 운영체제] Open GL Draw different shapes

Open GL의 기본적인 코드는

https://developer.android.com/develop/ui/views/graphics/opengl

위 사이트에 공개된 코드를 사용하였다.

---

 

MainActivity.java

package com.example.final_term_practice;

import android.opengl.GLSurfaceView;
import android.os.Bundle;
import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {

    private GLSurfaceView gLView;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // Create a GLSurfaceView instance and set it
        // as the ContentView for this Activity.
        gLView = new MyGLSurfaceView(this);
        setContentView(gLView);
    }

}

 

 

 

 

MyGLSurfaceView.java

package com.example.final_term_practice;

import android.content.Context;
import android.opengl.GLSurfaceView;

class MyGLSurfaceView extends GLSurfaceView {

    private final MyGLRenderer renderer;

    public MyGLSurfaceView(Context context){
        super(context);

        // Create an OpenGL ES 2.0 context
        setEGLContextClientVersion(2);

        renderer = new MyGLRenderer();

        // Set the Renderer for drawing on the GLSurfaceView
        setRenderer(renderer);
    }
}

 

 

 

 

 

MyGLRenderer.java

package com.example.final_term_practice;

import android.opengl.GLES20;
import android.opengl.GLSurfaceView;
import android.opengl.Matrix;

import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;

public class MyGLRenderer implements GLSurfaceView.Renderer {

    private Final_practice mClones;


    // vPMatrix is an abbreviation for "Model View Projection Matrix"
    private final float[] vPMatrix = new float[16];
    private final float[] projectionMatrix = new float[16];
    private final float[] viewMatrix = new float[16];


    public void onSurfaceCreated(GL10 unused, EGLConfig config) {
        // Set the background frame color
        GLES20.glClearColor(1.0f, 1.0f, 1.0f, 1.0f);

        // initialize a triangle
        mClones = new Final_practice();
    }

    public void onDrawFrame(GL10 unused) {
        // Redraw background color
        GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);

        // Set the camera position (View matrix)
        Matrix.setLookAtM(viewMatrix, 0, 0, 0, -3, 0f, 0f, 0f, 0f, 1.0f, 0.0f);

        // Calculate the projection and view transformation
        Matrix.multiplyMM(vPMatrix, 0, projectionMatrix, 0, viewMatrix, 0);

        // Draw shape
        mClones.draw(vPMatrix);

        // mTriangle.draw();
    }

    public void onSurfaceChanged(GL10 unused, int width, int height) {
        GLES20.glViewport(0, 0, width, height);

        float ratio = (float) width / height;

        // this projection matrix is applied to object coordinates
        // in the onDrawFrame() method
        Matrix.frustumM(projectionMatrix, 0, ratio, -ratio, -1, 1, 3, 7);

    }

    public static int loadShader(int type, String shaderCode){

        // create a vertex shader type (GLES20.GL_VERTEX_SHADER)
        // or a fragment shader type (GLES20.GL_FRAGMENT_SHADER)
        int shader = GLES20.glCreateShader(type);

        // add the source code to the shader and compile it
        GLES20.glShaderSource(shader, shaderCode);
        GLES20.glCompileShader(shader);

        return shader;
    }
}

 

 

 

 

 

Final_practice.java

package com.example.final_term_practice;

import android.opengl.GLES20;
import android.opengl.Matrix;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;

public class Final_practice {
    ///// Projection matrixes ////
    private final float[] mTranslateMatrix = new float[16];
    private final float[] mRotationMatrix = new float[16];
    private final float[] scratch = new float[16];
    private final float[] scratch_2 = new float[16];
    private final float[] scratch_3 = new float[16];
    private final float[] mRotationMatrix_new = new float[16];

    // Use to access and set the view transformation
    private int vPMatrixHandle;

    private FloatBuffer circleBuffer_1;

    private FloatBuffer circleBuffer_2;

    private FloatBuffer circleBuffer_3;

    private FloatBuffer bodyBuffer;


    private final int mProgram;

    private int positionHandle;
    private int colorHandle;


    private final int vertexStride = COORDS_PER_VERTEX * 4; // 4 bytes per vertex


    // number of coordinates per vertex in this array
    static final int COORDS_PER_VERTEX = 3;


    // Set color with red, green, blue and alpha (opacity) values
    float color_red[] = {1.0f, 0.0f, 0.0f, 1.0f};
    float color_black[] = {0.0f, 0.0f, 0.0f, 1.0f};
    float color_yellow[] = {1.0f, 1.0f, 0.0f, 1.0f};
    float color_gray[] = {0.8f, 0.8f, 0.8f, 1.0f};
    float color_white[] = {1.0f, 1.0f, 1.0f, 1.0f};


    static float circleCoords_1[] = new float[102 * COORDS_PER_VERTEX];

    //노란 사다리꼴의 좌표 (큰원의 반지름이 0.3이여서 지름은 0.6)
    float bodyCoords[] = {   // in counterclockwise order:
            0.2f, 0.7f, 0.0f,
            0.2f, 0.1f, 0.0f,
            -0.2f, 0.6f, 0.0f,
            -0.2f, 0.2f, 0.0f
    };

    public Final_practice() {

        int vertexShader = MyGLRenderer.loadShader(GLES20.GL_VERTEX_SHADER,
                vertexShaderCode);
        int fragmentShader = MyGLRenderer.loadShader(GLES20.GL_FRAGMENT_SHADER,
                fragmentShaderCode);

        // create empty OpenGL ES Program
        mProgram = GLES20.glCreateProgram();

        // add the vertex shader to program
        GLES20.glAttachShader(mProgram, vertexShader);

        // add the fragment shader to program
        GLES20.glAttachShader(mProgram, fragmentShader);

        // creates OpenGL ES program executables
        GLES20.glLinkProgram(mProgram);


        //큰 원 (오른쪽 위치)
        float R1 = 0.3f;
        float R2 = 0.3f;

        float x_center = 0.0f;
        float y_center = 0.0f;
        float dAngle = 2 * (float) Math.PI / (100);

        //// v0 /////
        circleCoords_1[0] = x_center;
        circleCoords_1[1] = y_center;
        circleCoords_1[2] = 0.0f;
        int index = 3;
        float angle;
        ///// 1st part
        for (angle = 0.0f; angle <= 2 * Math.PI + dAngle; angle = angle + dAngle) {
            circleCoords_1[index] = R1 * (float) Math.cos(angle);
            circleCoords_1[index + 1] = R2 * (float) Math.sin(angle);
            circleCoords_1[index + 2] = 0.0f;
            index = index + 3;
        }
        // initialize vertex byte buffer for shape coordinates
        ByteBuffer bb = ByteBuffer.allocateDirect(
                // (number of coordinate values * 4 bytes per float)
                circleCoords_1.length * 4);
        // use the device hardware's native byte order
        bb.order(ByteOrder.nativeOrder());

        // create a floating point buffer from the ByteBuffer
        circleBuffer_1 = bb.asFloatBuffer();
        // add the coordinates to the FloatBuffer
        circleBuffer_1.put(circleCoords_1);
        // set the buffer to read the first coordinate
        circleBuffer_1.position(0);

        //작은 원(왼쪽 위치), 하단에 위치한 회색 작은 원
        R1 = 0.2f;
        R2 = 0.2f;

        x_center = 0.0f;
        y_center = 0.0f;
        dAngle = 2 * (float) Math.PI / (100);

        //// v0 /////
        circleCoords_1[0] = x_center;
        circleCoords_1[1] = y_center;
        circleCoords_1[2] = 0.0f;
        index = 3;

        ///// 1st part
        for (angle = 0.0f; angle <= 2 * Math.PI + dAngle; angle = angle + dAngle) {
            circleCoords_1[index] = R1 * (float) Math.cos(angle);
            circleCoords_1[index + 1] = R2 * (float) Math.sin(angle);
            circleCoords_1[index + 2] = 0.0f;
            index = index + 3;
        }
        // initialize vertex byte buffer for shape coordinates
        ByteBuffer bb1 = ByteBuffer.allocateDirect(
                // (number of coordinate values * 4 bytes per float)
                circleCoords_1.length * 4);
        // use the device hardware's native byte order
        bb1.order(ByteOrder.nativeOrder());

        // create a floating point buffer from the ByteBuffer
        circleBuffer_2 = bb1.asFloatBuffer();
        // add the coordinates to the FloatBuffer
        circleBuffer_2.put(circleCoords_1);
        // set the buffer to read the first coordinate
        circleBuffer_2.position(0);

        //하단에 위치하게 될 작은 원 (하얀색)
        R1 = 0.1f;
        R2 = 0.1f;

        x_center = 0.0f;
        y_center = 0.0f;
        dAngle = 2 * (float) Math.PI / (100);

        //// v0 /////
        circleCoords_1[0] = x_center;
        circleCoords_1[1] = y_center;
        circleCoords_1[2] = 0.0f;
        index = 3;

        ///// 1st part
        for (angle = 0.0f; angle <= 2 * Math.PI + dAngle; angle = angle + dAngle) {
            circleCoords_1[index] = R1 * (float) Math.cos(angle);
            circleCoords_1[index + 1] = R2 * (float) Math.sin(angle);
            circleCoords_1[index + 2] = 0.0f;
            index = index + 3;
        }
        // initialize vertex byte buffer for shape coordinates
        ByteBuffer bb2 = ByteBuffer.allocateDirect(
                // (number of coordinate values * 4 bytes per float)
                circleCoords_1.length * 4);
        // use the device hardware's native byte order
        bb2.order(ByteOrder.nativeOrder());

        // create a floating point buffer from the ByteBuffer
        circleBuffer_3 = bb2.asFloatBuffer();
        // add the coordinates to the FloatBuffer
        circleBuffer_3.put(circleCoords_1);
        // set the buffer to read the first coordinate
        circleBuffer_3.position(0);


        ByteBuffer bb3 = ByteBuffer.allocateDirect(
                // (number of coordinate values * 4 bytes per float)
                bodyCoords.length * 4);
        // use the device hardware's native byte order
        bb3.order(ByteOrder.nativeOrder());

        // create a floating point buffer from the ByteBuffer
        bodyBuffer = bb3.asFloatBuffer();
        // add the coordinates to the FloatBuffer
        bodyBuffer.put(bodyCoords);
        // set the buffer to read the first coordinate
        bodyBuffer.position(0);

    }

    public void draw(float[] mvpMatrix) {
        // Add program to OpenGL ES environment
        GLES20.glUseProgram(mProgram);

        // get handle to vertex shader's vPosition member
        positionHandle = GLES20.glGetAttribLocation(mProgram, "vPosition");

        // Enable a handle to the triangle vertices
        GLES20.glEnableVertexAttribArray(positionHandle);

        // get handle to fragment shader's vColor member
        colorHandle = GLES20.glGetUniformLocation(mProgram, "vColor");

        // Set color for drawing the triangle


        // get handle to shape's transformation matrix
        vPMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uMVPMatrix");




        /// circle 1 (빨강 큰 원) //

        GLES20.glVertexAttribPointer(positionHandle, COORDS_PER_VERTEX,
                GLES20.GL_FLOAT, false,
                vertexStride, circleBuffer_1);

        Matrix.setIdentityM(mTranslateMatrix, 0);
        Matrix.setIdentityM(mRotationMatrix, 0);

        Matrix.translateM(mTranslateMatrix, 0, 0.2f, 0.4f, 0.0f); //빨강원이 위치할 위치 지정
        Matrix.setRotateM(mRotationMatrix, 0, 0.0f, 0, 0, -1.0f);
        //얼마나 회전할 건지 지정하는데 지금은 회전하지 않도록 설정

        //scratch, scratch_2가 어디에 들어가있는지 잘 확인 (최종 glUniformMatrix4fv여기에는 scratch_2가 들어가있음)
        Matrix.multiplyMM(scratch, 0, mvpMatrix, 0, mTranslateMatrix, 0);
        Matrix.multiplyMM(scratch_2, 0, scratch, 0, mRotationMatrix, 0);
        GLES20.glUniformMatrix4fv(vPMatrixHandle, 1, false, scratch_2, 0);

        //색 지정
        GLES20.glUniform4fv(colorHandle, 1, color_red, 0);

        // Draw the circle (102번 회전해서 원 만들 수 있게 해줌)
        GLES20.glDrawArrays(GLES20.GL_TRIANGLE_FAN, 0, 102);




        /// Circle 2 (빨강 작은 원)

        GLES20.glVertexAttribPointer(positionHandle, COORDS_PER_VERTEX,
                GLES20.GL_FLOAT, false,
                vertexStride, circleBuffer_2);

        Matrix.setIdentityM(mTranslateMatrix, 0);
        Matrix.setIdentityM(mRotationMatrix, 0);

        Matrix.translateM(mTranslateMatrix, 0, -0.2f, 0.4f, 0.0f); //작은원의 좌표를 지정
        Matrix.setRotateM(mRotationMatrix, 0, 0.0f, 0, 0, -1.0f);

        Matrix.multiplyMM(scratch, 0, mvpMatrix, 0, mTranslateMatrix, 0);
        Matrix.multiplyMM(scratch_2, 0, scratch, 0, mRotationMatrix, 0);
        GLES20.glUniformMatrix4fv(vPMatrixHandle, 1, false, scratch_2, 0);

        GLES20.glUniform4fv(colorHandle, 1, color_red, 0);

        // Draw the circle
        GLES20.glDrawArrays(GLES20.GL_TRIANGLE_FAN, 0, 102);






        /// Draw body (노랑 사다리꼴)///
        GLES20.glUniformMatrix4fv(vPMatrixHandle, 1, false, mvpMatrix, 0);

        GLES20.glVertexAttribPointer(positionHandle, COORDS_PER_VERTEX,
                GLES20.GL_FLOAT, false,
                vertexStride, bodyBuffer);

        GLES20.glUniform4fv(colorHandle, 1, color_yellow, 0);

        GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4); //FAN이 아닌 STRIP 사용





        ///// Figure 2 ///

        //// Central body - 하단 중심 회색 원///

        GLES20.glVertexAttribPointer(positionHandle, COORDS_PER_VERTEX,
                GLES20.GL_FLOAT, false,
                vertexStride, circleBuffer_2);

        Matrix.setIdentityM(mTranslateMatrix, 0);
        Matrix.setIdentityM(mRotationMatrix, 0);

        Matrix.translateM(mTranslateMatrix, 0, 0.0f, -0.5f, 0.0f); //좌표 설정
        Matrix.setRotateM(mRotationMatrix, 0, 0.0f, 0, 0, -1.0f);

        Matrix.multiplyMM(scratch, 0, mvpMatrix, 0, mTranslateMatrix, 0);
        Matrix.multiplyMM(scratch_2, 0, scratch, 0, mRotationMatrix, 0);
        GLES20.glUniformMatrix4fv(vPMatrixHandle, 1, false, scratch_2, 0);

        GLES20.glUniform4fv(colorHandle, 1, color_gray, 0);

        // Draw the circle
        GLES20.glDrawArrays(GLES20.GL_TRIANGLE_FAN, 0, 102);





        //// Cut part 1 북쪽 흰색 원///

        GLES20.glVertexAttribPointer(positionHandle, COORDS_PER_VERTEX,
                GLES20.GL_FLOAT, false,
                vertexStride, circleBuffer_3);

        Matrix.setIdentityM(mTranslateMatrix, 0);
        Matrix.setIdentityM(mRotationMatrix, 0);

        Matrix.translateM(mTranslateMatrix, 0, 0.0f, -0.3f, 0.0f); //좌표 설정
        Matrix.setRotateM(mRotationMatrix, 0, 0.0f, 0, 0, -1.0f);

        Matrix.multiplyMM(scratch, 0, mvpMatrix, 0, mTranslateMatrix, 0);
        Matrix.multiplyMM(scratch_2, 0, scratch, 0, mRotationMatrix, 0);
        GLES20.glUniformMatrix4fv(vPMatrixHandle, 1, false, scratch_2, 0);

        GLES20.glUniform4fv(colorHandle, 1, color_white, 0);

        // Draw the circle
        GLES20.glDrawArrays(GLES20.GL_TRIANGLE_FAN, 0, 102);




        //// Cut part 2 서쪽 흰색 원 ///

        Matrix.setIdentityM(mTranslateMatrix, 0);
        Matrix.setIdentityM(mRotationMatrix, 0);

        //회색 원을 중심으로 좌 우에 위치 하는거여서 y축은 동일하게 x축만 변경해줌
        Matrix.translateM(mTranslateMatrix, 0, -0.2f, -0.5f, 0.0f);
        Matrix.setRotateM(mRotationMatrix, 0, 0.0f, 0, 0, -1.0f);

        Matrix.multiplyMM(scratch, 0, mvpMatrix, 0, mTranslateMatrix, 0);
        Matrix.multiplyMM(scratch_2, 0, scratch, 0, mRotationMatrix, 0);
        GLES20.glUniformMatrix4fv(vPMatrixHandle, 1, false, scratch_2, 0);


        // Draw the circle
        GLES20.glDrawArrays(GLES20.GL_TRIANGLE_FAN, 0, 102);




        //// Cut part 3 남쪽 흰색 원///

        Matrix.setIdentityM(mTranslateMatrix, 0);
        Matrix.setIdentityM(mRotationMatrix, 0);

        Matrix.translateM(mTranslateMatrix, 0, 0.0f, -0.7f, 0.0f);
        Matrix.setRotateM(mRotationMatrix, 0, 0.0f, 0, 0, -1.0f);

        Matrix.multiplyMM(scratch, 0, mvpMatrix, 0, mTranslateMatrix, 0);
        Matrix.multiplyMM(scratch_2, 0, scratch, 0, mRotationMatrix, 0);
        GLES20.glUniformMatrix4fv(vPMatrixHandle, 1, false, scratch_2, 0);


        // Draw the circle
        GLES20.glDrawArrays(GLES20.GL_TRIANGLE_FAN, 0, 102);




        //// Cut part 4 동쪽 흰색 원///

        Matrix.setIdentityM(mTranslateMatrix, 0);
        Matrix.setIdentityM(mRotationMatrix, 0);

        Matrix.translateM(mTranslateMatrix, 0, 0.2f, -0.5f, 0.0f);
        Matrix.setRotateM(mRotationMatrix, 0, 0.0f, 0, 0, -1.0f);

        Matrix.multiplyMM(scratch, 0, mvpMatrix, 0, mTranslateMatrix, 0);
        Matrix.multiplyMM(scratch_2, 0, scratch, 0, mRotationMatrix, 0);
        GLES20.glUniformMatrix4fv(vPMatrixHandle, 1, false, scratch_2, 0);


        // Draw the circle
        GLES20.glDrawArrays(GLES20.GL_TRIANGLE_FAN, 0, 102);



        // Disable vertex array
        GLES20.glDisableVertexAttribArray(positionHandle);
    }

    private final String vertexShaderCode =
            // This matrix member variable provides a hook to manipulate
            // the coordinates of the objects that use this vertex shader
            "uniform mat4 uMVPMatrix;" +
                    "attribute vec4 vPosition;" +
                    "void main() {" +
                    // the matrix must be included as a modifier of gl_Position
                    // Note that the uMVPMatrix factor *must be first* in order
                    // for the matrix multiplication product to be correct.
                    "  gl_Position = uMVPMatrix * vPosition;" +
                    "}";


    private final String fragmentShaderCode =
            "precision mediump float;" +
                    "uniform vec4 vColor;" +
                    "void main() {" +
                    "  gl_FragColor = vColor;" +
                    "}";

}