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I'm new to OpenGL and trying to render multiple triangles using single VBO in using LWJGL3. I've followed demos and read some books and wrote following code, but its crashing. Without draw command it displays window with given background at least. I use vertex and fragment shader.

It prints following log and crashes. If I don't call glDrawArrays it never crashes and paints blue background:

0(6) : warning C7533: global variable gl_FragColor is deprecated after version 120

Fragment info
-------------
0(6) : warning C7533: global variable gl_FragColor is deprecated after version 120

Java Result: -1073741819

package mn.digz.lwjgl;

import static org.lwjgl.glfw.GLFW.*;
import static org.lwjgl.opengl.GL11.*;
import static org.lwjgl.opengl.GL15.*;
import static org.lwjgl.opengl.GL20.*;
import static org.lwjgl.system.MemoryUtil.NULL;

import java.io.IOException;
import java.nio.FloatBuffer;
import mn.digz.lwjgl.ShaderUtil;

import org.joml.Matrix4f;
import org.lwjgl.BufferUtils;
import org.lwjgl.glfw.GLFWErrorCallback;
import org.lwjgl.glfw.GLFWFramebufferSizeCallback;
import org.lwjgl.glfw.GLFWKeyCallback;
import org.lwjgl.glfw.GLFWVidMode;
import org.lwjgl.opengl.GL;
import org.lwjgl.opengl.GLCapabilities;
import org.lwjgl.opengl.GLUtil;
import org.lwjgl.system.Callback;

/**
 *
 * @author MethoD
 */
public class OpenGLGraphRender {

    long window;
    int width = 1024;
    int height = 768;

    int vao;
    int program;

    int viewProjMatrixUniform;

    Matrix4f viewProjMatrix = new Matrix4f();
    FloatBuffer matrixBuffer = BufferUtils.createFloatBuffer(16);

    FloatBuffer verticesBuffer;
    int vertexPositionAttribute;
    int vertexColorAttribute;
    int pointSize = 3 + 4; // x,y,z + r,g,b,a
    int step = 4; // byte per element
    int stride = step * pointSize; // need?

    GLCapabilities caps;
    GLFWErrorCallback errCallback;
    Callback debugProc;

    void init() throws IOException {
        glfwSetErrorCallback(errCallback = new GLFWErrorCallback() {
            GLFWErrorCallback delegate = GLFWErrorCallback.createPrint(System.err);

            @Override
            public void invoke(int error, long description) {
                if (error == GLFW_VERSION_UNAVAILABLE)
                    System.err.println("This demo requires OpenGL 2.0 or higher.");
                delegate.invoke(error, description);
            }

            @Override
            public void free() {
                delegate.free();
            }
        });

        if (!glfwInit())
            throw new IllegalStateException("Unable to initialize GLFW");

        glfwDefaultWindowHints();
        glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 2);
        glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
        glfwWindowHint(GLFW_VISIBLE, GLFW_FALSE);
        glfwWindowHint(GLFW_RESIZABLE, GLFW_TRUE);

        window = glfwCreateWindow(width, height, "Silhouette rendering with geometry shader", NULL, NULL);
        if (window == NULL) {
            throw new AssertionError("Failed to create the GLFW window");
        }

        GLFWVidMode vidmode = glfwGetVideoMode(glfwGetPrimaryMonitor());
        glfwSetWindowPos(window, (vidmode.width() - width) / 2, (vidmode.height() - height) / 2);
        glfwMakeContextCurrent(window);
        glfwSwapInterval(0);
        glfwShowWindow(window);
        caps = GL.createCapabilities();
        /*if (!caps.GL_EXT_geometry_shader4) {
            throw new AssertionError("This demo requires the EXT_geometry_shader4 extension");
        }*/

        debugProc = GLUtil.setupDebugMessageCallback();

        glClearColor(0.55f, 0.75f, 0.95f, 1.0f);
        glEnable(GL_DEPTH_TEST);

        /* Create all needed GL resources */
        createTriangleVao();
        createRasterProgram();
        initProgram();
    }

    void createTriangleVao() {
        verticesBuffer = BufferUtils.createFloatBuffer(pointSize * 3 * 3); // point size * 3 points * 3 triangles = 21 floats per triangle
        verticesBuffer.put(new float[] {0f, 0f, 0f, 1f, 1f, 0f, 1f, 2f, 0f, 0f, 1f, 1f, 0f, 1f, 1f, 1.7f, 0f, 1f, 1f, 0f, 1f});
        verticesBuffer.put(new float[] {4f, 4f, 0f, 1f, 1f, 0f, 1f, 6f, 4f, 0f, 1f, 1f, 0f, 1f, 5f, 5.7f, 0f, 1f, 1f, 0f, 1f});
        verticesBuffer.put(new float[] {4f, 1f, 0f, 1f, 1f, 0f, 1f, 6f, 1f, 0f, 1f, 1f, 0f, 1f, 5f, 2.7f, 0f, 1f, 1f, 0f, 1f});

        int vbo = glGenBuffers();
        glBindBuffer(GL_ARRAY_BUFFER, vbo);
        glBufferData(GL_ARRAY_BUFFER, verticesBuffer, GL_STATIC_DRAW);
        glVertexAttribPointer(vertexPositionAttribute, 3, GL_FLOAT, false, stride, 0);
        glVertexAttribPointer(vertexColorAttribute, 4, GL_FLOAT, false, stride, step * 3);
    }

    void createRasterProgram() throws IOException {
        int program = glCreateProgram();
        int vshader = ShaderUtil.createShader("mn/digz/lwjgl/shader/vs.glsl", GL_VERTEX_SHADER);
        int fshader = ShaderUtil.createShader("mn/digz/lwjgl/shader/fs.glsl", GL_FRAGMENT_SHADER);
        glAttachShader(program, vshader);
        glAttachShader(program, fshader);

        glLinkProgram(program);
        int linked = glGetProgrami(program, GL_LINK_STATUS);
        String programLog = glGetProgramInfoLog(program);
        if (programLog != null && programLog.trim().length() > 0) {
            System.err.println(programLog);
        }
        if (linked == 0) {
            throw new AssertionError("Could not link program");
        }
        this.program = program;
    }

    /**
     * Initialize the shader program.
     */
    void initProgram() {
        glUseProgram(this.program);
        viewProjMatrixUniform = glGetUniformLocation(this.program, "viewProjMatrix");

        glBindAttribLocation(program, 0, "vertexPosition");
        glBindAttribLocation(program, 0, "vertexColor");
        vertexPositionAttribute = glGetAttribLocation(program, "vertexPosition");
        glEnableVertexAttribArray(vertexPositionAttribute);
        vertexColorAttribute = glGetAttribLocation(program, "vertexColor");
        glEnableVertexAttribArray(vertexColorAttribute);

        glUseProgram(0);
    }

    void update() {
        viewProjMatrix
            .setPerspective((float) Math.toRadians(30), (float) width / height, 0.01f, 50.0f)
            .lookAt(0.0f, 2.0f, 7.0f,
                    0.0f, 0.0f, 0.0f,
                    0.0f, 1.0f, 0.0f);
    }

    void render() {
        glUseProgram(this.program);
        glUniformMatrix4fv(viewProjMatrixUniform, false, viewProjMatrix.get(matrixBuffer));

        //int numItems = verticesBuffer.array().length / pointSize;
        int numItems = 3;
        glDrawArrays(GL_TRIANGLES, 0, numItems);

        glUseProgram(0);
    }

    void loop() {
        while (!glfwWindowShouldClose(window)) {
            glfwPollEvents();
            glViewport(0, 0, width, height);
            glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

            update();
            render();

            glfwSwapBuffers(window);
        }
    }

    void run() {
        try {
            init();
            loop();

            if (debugProc != null)
                debugProc.free();
            errCallback.free();
            glfwDestroyWindow(window);
        } catch (Throwable t) {
            t.printStackTrace();
        } finally {
            glfwTerminate();
        }
    }

    public static void main(String[] args) {
        new OpenGLGraphRender().run();
    }
}

I'm new to OpenGL and trying to render multiple triangles using single VBO in using LWJGL3. I've followed demos and read some books and wrote following code, but its not drawing my shape. I use vertex and fragment shader.

It prints following log and not drawing anything.

0(6) : warning C7533: global variable gl_FragColor is deprecated after version 120

Fragment info
-------------
0(6) : warning C7533: global variable gl_FragColor is deprecated after version 120

[LWJGL] OpenGL debug message
    ID: 0x20071
    Source: API
    Type: OTHER
    Severity: NOTIFICATION
    Message: Buffer detailed info: Buffer object 1 (bound to GL_ARRAY_BUFFER_ARB, usage hint is GL_STATIC_DRAW) will use VIDEO memory as the source for buffer object operations.

package mn.digz.lwjgl;

import static org.lwjgl.glfw.GLFW.*;
import static org.lwjgl.opengl.GL11.*;
import static org.lwjgl.opengl.GL15.*;
import static org.lwjgl.opengl.GL20.*;
import static org.lwjgl.system.MemoryUtil.NULL;

import java.io.IOException;
import java.nio.FloatBuffer;
import mn.astvision.assetmanagement.lib.lwjgl.util.ShaderUtil;

import org.joml.Matrix4f;
import org.lwjgl.BufferUtils;
import org.lwjgl.glfw.GLFWErrorCallback;
import org.lwjgl.glfw.GLFWVidMode;
import org.lwjgl.opengl.GL;
import org.lwjgl.opengl.GLCapabilities;
import org.lwjgl.opengl.GLUtil;
import org.lwjgl.system.Callback;

/**
 *
 * @author MethoD
 */
public class OpenGLGraphRender {

    long window;
    int width = 1024;
    int height = 768;

    int vao;
    int program;

    int viewProjMatrixUniform;

    Matrix4f viewProjMatrix = new Matrix4f();
    FloatBuffer matrixBuffer = BufferUtils.createFloatBuffer(16);

    FloatBuffer verticesBuffer;
    int vertexPositionAttribute;
    int vertexColorAttribute;
    int pointSize = 3 + 4; // x,y,z + r,g,b,a
    int step = Float.SIZE / 8; // byte per element
    int stride = step * pointSize; // need?

    GLFWErrorCallback errCallback;
    Callback debugProc;

    void init() {
        glfwSetErrorCallback(errCallback = GLFWErrorCallback.createPrint(System.err));

        if (!glfwInit())
            throw new IllegalStateException("Unable to initialize GLFW");

        glfwDefaultWindowHints();
        glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 2);
        glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
        glfwWindowHint(GLFW_VISIBLE, GLFW_FALSE);
        glfwWindowHint(GLFW_RESIZABLE, GLFW_TRUE);

        window = glfwCreateWindow(width, height, "Silhouette rendering with geometry shader", NULL, NULL);
        if (window == NULL) {
            throw new AssertionError("Failed to create the GLFW window");
        }

        GLFWVidMode vidmode = glfwGetVideoMode(glfwGetPrimaryMonitor());
        glfwSetWindowPos(window, (vidmode.width() - width) / 2, (vidmode.height() - height) / 2);
        glfwMakeContextCurrent(window);
        glfwSwapInterval(1); // enable v sync
        glfwShowWindow(window);
    }

    void createProgram() throws IOException {
        int program = glCreateProgram();
        int vshader = ShaderUtil.createShader("mn/astvision/assetmanagement/lib/lwjgl/shader/vs.glsl", GL_VERTEX_SHADER);
        int fshader = ShaderUtil.createShader("mn/astvision/assetmanagement/lib/lwjgl/shader/fs.glsl", GL_FRAGMENT_SHADER);
        glAttachShader(program, vshader);
        glAttachShader(program, fshader);

        glLinkProgram(program);
        int linked = glGetProgrami(program, GL_LINK_STATUS);
        String programLog = glGetProgramInfoLog(program);
        if (programLog != null && programLog.trim().length() > 0) {
            System.err.println(programLog);
        }
        if (linked == 0) {
            throw new AssertionError("Could not link program");
        }
        this.program = program;
    }

    /**
     * Initialize the shader program.
     */
    void initProgram() {
        glUseProgram(this.program);
        viewProjMatrixUniform = glGetUniformLocation(this.program, "viewProjMatrix");

        glBindAttribLocation(program, 0, "vertexPosition");
        glBindAttribLocation(program, 0, "vertexColor");
        vertexPositionAttribute = glGetAttribLocation(program, "vertexPosition");
        vertexColorAttribute = glGetAttribLocation(program, "vertexColor");

        verticesBuffer = BufferUtils.createFloatBuffer(pointSize * 3 * 3); // point size * 3 points * 3 triangles = 21 floats per triangle
        verticesBuffer.put(new float[] {0f, 0f, 0f, 1f, 1f, 0f, 1f, 2f, 0f, 0f, 1f, 1f, 0f, 1f, 1f, 1.7f, 0f, 1f, 1f, 0f, 1f});
        verticesBuffer.put(new float[] {4f, 4f, 0f, 1f, 1f, 0f, 1f, 6f, 4f, 0f, 1f, 1f, 0f, 1f, 5f, 5.7f, 0f, 1f, 1f, 0f, 1f});
        verticesBuffer.put(new float[] {4f, 1f, 0f, 1f, 1f, 0f, 1f, 6f, 1f, 0f, 1f, 1f, 0f, 1f, 5f, 2.7f, 0f, 1f, 1f, 0f, 1f});
        verticesBuffer.flip();

        int vbo = glGenBuffers();
        glBindBuffer(GL_ARRAY_BUFFER, vbo);
        glBufferData(GL_ARRAY_BUFFER, verticesBuffer, GL_STATIC_DRAW);

        glVertexAttribPointer(vertexPositionAttribute, 3, GL_FLOAT, false, stride, 0);
        glVertexAttribPointer(vertexColorAttribute, 4, GL_FLOAT, false, stride, step * 3);
        glEnableVertexAttribArray(vertexPositionAttribute);
        glEnableVertexAttribArray(vertexColorAttribute);

        glUseProgram(0);
    }

    void render() {
        viewProjMatrix
            .setPerspective((float) Math.toRadians(30), (float) width / height, 0.01f, 50.0f)
            .lookAt(0.0f, 2.0f, 7.0f,
                    0.0f, 0.0f, 0.0f,
                    0.0f, 1.0f, 0.0f);

        glUseProgram(this.program);
        glUniformMatrix4fv(viewProjMatrixUniform, false, viewProjMatrix.get(matrixBuffer));

        int numItems = 3;
        glDrawArrays(GL_TRIANGLES, 0, numItems);

        glUseProgram(0);
    }

    void loop() throws IOException {
        GL.createCapabilities();

        debugProc = GLUtil.setupDebugMessageCallback();

        glClearColor(0.55f, 0.75f, 0.95f, 1.0f);
        glEnable(GL_DEPTH_TEST);

        /* Create all needed GL resources */
        createProgram();
        initProgram();

        while (!glfwWindowShouldClose(window)) {
            glfwPollEvents();
            glViewport(0, 0, width, height);
            glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

            render();

            glfwSwapBuffers(window);
        }
    }

    void run() {
        try {
            init();
            loop();

            if (debugProc != null)
                debugProc.free();
            errCallback.free();
            glfwDestroyWindow(window);
        } catch (Throwable t) {
            t.printStackTrace();
        } finally {
            glfwTerminate();
        }
    }
}

It prints following log and crashes:

It prints following log and crashes. If I don't call glDrawArrays it never crashes and paints blue background:

I'm new to OpenGL and trying to render multiple triangles using single VBO in using LWJGL3. I've followed demos and read some books and wrote following code, but its crashing. Without draw command it displays window with given background at least. I use vertex and fragment shader.

package mn.digz.lwjgl;

import static org.lwjgl.glfw.GLFW.*;
import static org.lwjgl.opengl.GL11.*;
import static org.lwjgl.opengl.GL15.*;
import static org.lwjgl.opengl.GL20.*;
import static org.lwjgl.system.MemoryUtil.NULL;

import java.io.IOException;
import java.nio.FloatBuffer;
import mn.digz.lwjgl.ShaderUtil;

import org.joml.Matrix4f;
import org.lwjgl.BufferUtils;
import org.lwjgl.glfw.GLFWErrorCallback;
import org.lwjgl.glfw.GLFWFramebufferSizeCallback;
import org.lwjgl.glfw.GLFWKeyCallback;
import org.lwjgl.glfw.GLFWVidMode;
import org.lwjgl.opengl.GL;
import org.lwjgl.opengl.GLCapabilities;
import org.lwjgl.opengl.GLUtil;
import org.lwjgl.system.Callback;

/**
 *
 * @author MethoD
 */
public class OpenGLGraphRender {

    long window;
    int width = 1024;
    int height = 768;

    int vao;
    int program;

    int viewProjMatrixUniform;

    Matrix4f viewProjMatrix = new Matrix4f();
    FloatBuffer matrixBuffer = BufferUtils.createFloatBuffer(16);

    FloatBuffer verticesBuffer;
    int vertexPositionAttribute;
    int vertexColorAttribute;
    int pointSize = 3 + 4; // x,y,z + r,g,b,a
    int step = 4; // byte per element
    int stride = step * pointSize; // need?

    GLCapabilities caps;
    GLFWErrorCallback errCallback;
    GLFWKeyCallback keyCallback;
    GLFWFramebufferSizeCallback fbCallback;
    Callback debugProc;

    void init() throws IOException {
        glfwSetErrorCallback(errCallback = new GLFWErrorCallback() {
            GLFWErrorCallback delegate = GLFWErrorCallback.createPrint(System.err);

            @Override
            public void invoke(int error, long description) {
                if (error == GLFW_VERSION_UNAVAILABLE)
                    System.err.println("This demo requires OpenGL 2.0 or higher.");
                delegate.invoke(error, description);
            }

            @Override
            public void free() {
                delegate.free();
            }
        });

        if (!glfwInit())
            throw new IllegalStateException("Unable to initialize GLFW");

        glfwDefaultWindowHints();
        glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 2);
        glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
        glfwWindowHint(GLFW_VISIBLE, GLFW_FALSE);
        glfwWindowHint(GLFW_RESIZABLE, GLFW_TRUE);

        window = glfwCreateWindow(width, height, "Silhouette rendering with geometry shader", NULL, NULL);
        if (window == NULL) {
            throw new AssertionError("Failed to create the GLFW window");
        }

        glfwSetFramebufferSizeCallback(window, fbCallback = new GLFWFramebufferSizeCallback() {
            @Override
            public void invoke(long window, int width, int height) {
                if (width > 0 && height > 0
                        && (OpenGLGraphRender.this.width != width || OpenGLGraphRender.this.height != height)) {
                    OpenGLGraphRender.this.width = width;
                    OpenGLGraphRender.this.height = height;
                }
            }
        });

        glfwSetKeyCallback(window, keyCallback = new GLFWKeyCallback() {
            @Override
            public void invoke(long window, int key, int scancode, int action, int mods) {
                if (action != GLFW_RELEASE)
                    return;

                if (key == GLFW_KEY_ESCAPE) {
                    glfwSetWindowShouldClose(window, true);
                }
            }
        });

        GLFWVidMode vidmode = glfwGetVideoMode(glfwGetPrimaryMonitor());
        glfwSetWindowPos(window, (vidmode.width() - width) / 2, (vidmode.height() - height) / 2);
        glfwMakeContextCurrent(window);
        glfwSwapInterval(0);
        glfwShowWindow(window);
        caps = GL.createCapabilities();
        /*if (!caps.GL_EXT_geometry_shader4) {
            throw new AssertionError("This demo requires the EXT_geometry_shader4 extension");
        }*/

        debugProc = GLUtil.setupDebugMessageCallback();

        glClearColor(0.55f, 0.75f, 0.95f, 1.0f);
        glEnable(GL_DEPTH_TEST);

        /* Create all needed GL resources */
        createTriangleVao();
        createRasterProgram();
        initProgram();
    }

    void createTriangleVao() {
        verticesBuffer = BufferUtils.createFloatBuffer(pointSize * 3 * 3); // point size * 3 points * 3 triangles = 21 floats per triangle
        verticesBuffer.put(new float[] {0f, 0f, 0f, 1f, 1f, 0f, 1f, 2f, 0f, 0f, 1f, 1f, 0f, 1f, 1f, 1.7f, 0f, 1f, 1f, 0f, 1f});
        verticesBuffer.put(new float[] {4f, 4f, 0f, 1f, 1f, 0f, 1f, 6f, 4f, 0f, 1f, 1f, 0f, 1f, 5f, 5.7f, 0f, 1f, 1f, 0f, 1f});
        verticesBuffer.put(new float[] {4f, 1f, 0f, 1f, 1f, 0f, 1f, 6f, 1f, 0f, 1f, 1f, 0f, 1f, 5f, 2.7f, 0f, 1f, 1f, 0f, 1f});

        int vbo = glGenBuffers();
        glBindBuffer(GL_ARRAY_BUFFER, vbo);
        glBufferData(GL_ARRAY_BUFFER, verticesBuffer, GL_STATIC_DRAW);
        glVertexAttribPointer(vertexPositionAttribute, 3, GL_FLOAT, false, stride, 0);
        glVertexAttribPointer(vertexColorAttribute, 4, GL_FLOAT, false, stride, step * 3);
    }

    void createRasterProgram() throws IOException {
        int program = glCreateProgram();
        int vshader = ShaderUtil.createShader("mn/digz/lwjgl/shader/vs.glsl", GL_VERTEX_SHADER);
        int fshader = ShaderUtil.createShader("mn/digz/lwjgl/shader/fs.glsl", GL_FRAGMENT_SHADER);
        glAttachShader(program, vshader);
        glAttachShader(program, fshader);

        glLinkProgram(program);
        int linked = glGetProgrami(program, GL_LINK_STATUS);
        String programLog = glGetProgramInfoLog(program);
        if (programLog != null && programLog.trim().length() > 0) {
            System.err.println(programLog);
        }
        if (linked == 0) {
            throw new AssertionError("Could not link program");
        }
        this.program = program;
    }

    /**
     * Initialize the shader program.
     */
    void initProgram() {
        glUseProgram(this.program);
        viewProjMatrixUniform = glGetUniformLocation(this.program, "viewProjMatrix");

        glBindAttribLocation(program, 0, "vertexPosition");
        glBindAttribLocation(program, 0, "vertexColor");
        vertexPositionAttribute = glGetAttribLocation(program, "vertexPosition");
        glEnableVertexAttribArray(vertexPositionAttribute);
        vertexColorAttribute = glGetAttribLocation(program, "vertexColor");
        glEnableVertexAttribArray(vertexColorAttribute);

        glUseProgram(0);
    }

    void update() {
        viewProjMatrix
            .setPerspective((float) Math.toRadians(30), (float) width / height, 0.01f, 50.0f)
            .lookAt(0.0f, 2.0f, 7.0f,
                    0.0f, 0.0f, 0.0f,
                    0.0f, 1.0f, 0.0f);
    }

    void render() {
        glUseProgram(this.program);
        glUniformMatrix4fv(viewProjMatrixUniform, false, viewProjMatrix.get(matrixBuffer));

        //int numItems = verticesBuffer.array().length / pointSize;
        int numItems = 3;
        glDrawArrays(GL_TRIANGLES, 0, numItems);

        glUseProgram(0);
    }

    void loop() {
        while (!glfwWindowShouldClose(window)) {
            glfwPollEvents();
            glViewport(0, 0, width, height);
            glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

            update();
            render();

            glfwSwapBuffers(window);
        }
    }

    void run() {
        try {
            init();
            loop();

            if (debugProc != null)
                debugProc.free();
            errCallback.free();
            keyCallback.free();
            fbCallback.free();
            glfwDestroyWindow(window);
        } catch (Throwable t) {
            t.printStackTrace();
        } finally {
            glfwTerminate();
        }
    }

    public static void main(String[] args) {
        new OpenGLGraphRender().run();
    }
}

I'm new to OpenGL and trying to render multiple triangles using single VBO in using LWJGL3. I've followed demos and read some books and wrote following code, but its crashing. Without draw command it displays window with given background at least. I use vertex and fragment shader.

It prints following log and crashes:

0(6) : warning C7533: global variable gl_FragColor is deprecated after version 120

Fragment info
-------------
0(6) : warning C7533: global variable gl_FragColor is deprecated after version 120

Java Result: -1073741819

Here's the source code of runnable class:

package mn.digz.lwjgl;

import static org.lwjgl.glfw.GLFW.*;
import static org.lwjgl.opengl.GL11.*;
import static org.lwjgl.opengl.GL15.*;
import static org.lwjgl.opengl.GL20.*;
import static org.lwjgl.system.MemoryUtil.NULL;

import java.io.IOException;
import java.nio.FloatBuffer;
import mn.digz.lwjgl.ShaderUtil;

import org.joml.Matrix4f;
import org.lwjgl.BufferUtils;
import org.lwjgl.glfw.GLFWErrorCallback;
import org.lwjgl.glfw.GLFWFramebufferSizeCallback;
import org.lwjgl.glfw.GLFWKeyCallback;
import org.lwjgl.glfw.GLFWVidMode;
import org.lwjgl.opengl.GL;
import org.lwjgl.opengl.GLCapabilities;
import org.lwjgl.opengl.GLUtil;
import org.lwjgl.system.Callback;

/**
 *
 * @author MethoD
 */
public class OpenGLGraphRender {

    long window;
    int width = 1024;
    int height = 768;

    int vao;
    int program;

    int viewProjMatrixUniform;

    Matrix4f viewProjMatrix = new Matrix4f();
    FloatBuffer matrixBuffer = BufferUtils.createFloatBuffer(16);

    FloatBuffer verticesBuffer;
    int vertexPositionAttribute;
    int vertexColorAttribute;
    int pointSize = 3 + 4; // x,y,z + r,g,b,a
    int step = 4; // byte per element
    int stride = step * pointSize; // need?

    GLCapabilities caps;
    GLFWErrorCallback errCallback;
    Callback debugProc;

    void init() throws IOException {
        glfwSetErrorCallback(errCallback = new GLFWErrorCallback() {
            GLFWErrorCallback delegate = GLFWErrorCallback.createPrint(System.err);

            @Override
            public void invoke(int error, long description) {
                if (error == GLFW_VERSION_UNAVAILABLE)
                    System.err.println("This demo requires OpenGL 2.0 or higher.");
                delegate.invoke(error, description);
            }

            @Override
            public void free() {
                delegate.free();
            }
        });

        if (!glfwInit())
            throw new IllegalStateException("Unable to initialize GLFW");

        glfwDefaultWindowHints();
        glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 2);
        glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
        glfwWindowHint(GLFW_VISIBLE, GLFW_FALSE);
        glfwWindowHint(GLFW_RESIZABLE, GLFW_TRUE);

        window = glfwCreateWindow(width, height, "Silhouette rendering with geometry shader", NULL, NULL);
        if (window == NULL) {
            throw new AssertionError("Failed to create the GLFW window");
        }

        GLFWVidMode vidmode = glfwGetVideoMode(glfwGetPrimaryMonitor());
        glfwSetWindowPos(window, (vidmode.width() - width) / 2, (vidmode.height() - height) / 2);
        glfwMakeContextCurrent(window);
        glfwSwapInterval(0);
        glfwShowWindow(window);
        caps = GL.createCapabilities();
        /*if (!caps.GL_EXT_geometry_shader4) {
            throw new AssertionError("This demo requires the EXT_geometry_shader4 extension");
        }*/

        debugProc = GLUtil.setupDebugMessageCallback();

        glClearColor(0.55f, 0.75f, 0.95f, 1.0f);
        glEnable(GL_DEPTH_TEST);

        /* Create all needed GL resources */
        createTriangleVao();
        createRasterProgram();
        initProgram();
    }

    void createTriangleVao() {
        verticesBuffer = BufferUtils.createFloatBuffer(pointSize * 3 * 3); // point size * 3 points * 3 triangles = 21 floats per triangle
        verticesBuffer.put(new float[] {0f, 0f, 0f, 1f, 1f, 0f, 1f, 2f, 0f, 0f, 1f, 1f, 0f, 1f, 1f, 1.7f, 0f, 1f, 1f, 0f, 1f});
        verticesBuffer.put(new float[] {4f, 4f, 0f, 1f, 1f, 0f, 1f, 6f, 4f, 0f, 1f, 1f, 0f, 1f, 5f, 5.7f, 0f, 1f, 1f, 0f, 1f});
        verticesBuffer.put(new float[] {4f, 1f, 0f, 1f, 1f, 0f, 1f, 6f, 1f, 0f, 1f, 1f, 0f, 1f, 5f, 2.7f, 0f, 1f, 1f, 0f, 1f});

        int vbo = glGenBuffers();
        glBindBuffer(GL_ARRAY_BUFFER, vbo);
        glBufferData(GL_ARRAY_BUFFER, verticesBuffer, GL_STATIC_DRAW);
        glVertexAttribPointer(vertexPositionAttribute, 3, GL_FLOAT, false, stride, 0);
        glVertexAttribPointer(vertexColorAttribute, 4, GL_FLOAT, false, stride, step * 3);
    }

    void createRasterProgram() throws IOException {
        int program = glCreateProgram();
        int vshader = ShaderUtil.createShader("mn/digz/lwjgl/shader/vs.glsl", GL_VERTEX_SHADER);
        int fshader = ShaderUtil.createShader("mn/digz/lwjgl/shader/fs.glsl", GL_FRAGMENT_SHADER);
        glAttachShader(program, vshader);
        glAttachShader(program, fshader);

        glLinkProgram(program);
        int linked = glGetProgrami(program, GL_LINK_STATUS);
        String programLog = glGetProgramInfoLog(program);
        if (programLog != null && programLog.trim().length() > 0) {
            System.err.println(programLog);
        }
        if (linked == 0) {
            throw new AssertionError("Could not link program");
        }
        this.program = program;
    }

    /**
     * Initialize the shader program.
     */
    void initProgram() {
        glUseProgram(this.program);
        viewProjMatrixUniform = glGetUniformLocation(this.program, "viewProjMatrix");

        glBindAttribLocation(program, 0, "vertexPosition");
        glBindAttribLocation(program, 0, "vertexColor");
        vertexPositionAttribute = glGetAttribLocation(program, "vertexPosition");
        glEnableVertexAttribArray(vertexPositionAttribute);
        vertexColorAttribute = glGetAttribLocation(program, "vertexColor");
        glEnableVertexAttribArray(vertexColorAttribute);

        glUseProgram(0);
    }

    void update() {
        viewProjMatrix
            .setPerspective((float) Math.toRadians(30), (float) width / height, 0.01f, 50.0f)
            .lookAt(0.0f, 2.0f, 7.0f,
                    0.0f, 0.0f, 0.0f,
                    0.0f, 1.0f, 0.0f);
    }

    void render() {
        glUseProgram(this.program);
        glUniformMatrix4fv(viewProjMatrixUniform, false, viewProjMatrix.get(matrixBuffer));

        //int numItems = verticesBuffer.array().length / pointSize;
        int numItems = 3;
        glDrawArrays(GL_TRIANGLES, 0, numItems);

        glUseProgram(0);
    }

    void loop() {
        while (!glfwWindowShouldClose(window)) {
            glfwPollEvents();
            glViewport(0, 0, width, height);
            glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

            update();
            render();

            glfwSwapBuffers(window);
        }
    }

    void run() {
        try {
            init();
            loop();

            if (debugProc != null)
                debugProc.free();
            errCallback.free();
            glfwDestroyWindow(window);
        } catch (Throwable t) {
            t.printStackTrace();
        } finally {
            glfwTerminate();
        }
    }

    public static void main(String[] args) {
        new OpenGLGraphRender().run();
    }
}