问题
I am little bit desperate here. I am trying to update/refactor an existing code written in legacy opengl to make use of the "modern way" of opengl version 3.2+.
It is written in Java with lwjgl. I already stripped away most of the functionality to test the basic setup. For me at the moment it is really just about setting up the vbo with vertices loaded from an obj file and render it. My problem is, that the display window stays empty. If it would display me just something, I would be really happy.
Maybe you guys can help me what I am missing here.
public class Mobile {
private final String texturePath = "../CGSS15Ex3MobileDS/dataEx3/Textures";
private int
width = 1200,
height = 800,
fps = 0,
cameraDist = 2000,
fillMode = GL_LINE,
ticksPerSecond = 60,
frameCounter = 0,
vaoId,
vboId,
vboiID,
pId,
vsId,
fsId;
private long
time,
lastTime,
lastFPS,
lastKeySpace,
frameCounterTime,
avgTime = 0;
private float
dx = 0f, // mouse x distance
dy = 0f, // mouse y distance
diffTime = 0f, // frame length
mouseSensitivity = 0.5f,
movementSpeed = 800.0f; // move 10 units per second.
private Fork fork;
private CameraController camera;
FloatBuffer kugelBuff, indexBuff;
int kugelVertCount;
static LinkedList<Integer> textureIDs = new LinkedList<>();
public Mobile() {
run();
}
private void run() {
init();
while (!exit()) {
update();
draw();
updateFPS();
}
fini();
}
private void init() {
// OpenGL Setup
// create display
try {
PixelFormat pixelFormat = new PixelFormat();
ContextAttribs contextAtrributes = new ContextAttribs(3, 2)
.withProfileCore(true)
.withForwardCompatible(true);
Display.setDisplayMode(new DisplayMode(width, height));
Display.setTitle("Mobile by Aaron Scheu");
Display.create(pixelFormat, contextAtrributes);
GL11.glClearColor(0.3f, 0.3f, 0.3f, 0f);
GL11.glViewport(0, 0, width, height);
} catch (LWJGLException e) {
e.printStackTrace();
System.exit(-1);
}
// setup scene //
setupSphere();
setupShaders();
setupTex();
// set Timer
frameCounterTime = lastFPS = getTime();
System.out.println("Start timer ...");
}
private void setupTex() {
for (String file : getTextureFiles(texturePath)) {
try {
TextureReader.Texture texture = TextureReader.readTexture(file);
textureIDs.add(glGenTextures());
GL13.glActiveTexture(GL13.GL_TEXTURE0);
GL11.glBindTexture(GL11.GL_TEXTURE_2D, textureIDs.getLast());
// Upload tex and generate mipmap for scaling
glTexImage2D(
GL_TEXTURE_2D, 0, GL_RGB, texture.getWidth(), texture.getHeight(), 0,
GL_RGB, GL_UNSIGNED_BYTE, texture.getPixels()
);
GL30.glGenerateMipmap(GL11.GL_TEXTURE_2D);
// Setup the ST coordinate system
GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_WRAP_S, GL11.GL_REPEAT);
GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_WRAP_T, GL11.GL_REPEAT);
// Setup what to do when the texture has to be scaled
GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_MAG_FILTER,
GL11.GL_NEAREST);
GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_MIN_FILTER,
GL11.GL_LINEAR_MIPMAP_LINEAR);
} catch(IOException e) {
System.out.println(e);
}
}
}
private void setupShaders() {
// Load the vertex shader
// vsId = GLDrawHelper.compileShader("../CGSS15Ex3MobileDS/dataEx3/Shader/phong_vertex.glsl", GL20.GL_VERTEX_SHADER);
vsId = GLDrawHelper.compileShader("shader/vert_shader.glsl", GL20.GL_VERTEX_SHADER);
// Load the fragment shader
// fsId = GLDrawHelper.compileShader("../CGSS15Ex3MobileDS/dataEx3/Shader/phong_fragment.glsl", GL20.GL_FRAGMENT_SHADER);
fsId = GLDrawHelper.compileShader("shader/frac_shader.glsl", GL20.GL_FRAGMENT_SHADER);
// Create a new shader program that links both shaders
pId = GL20.glCreateProgram();
GL20.glAttachShader(pId, vsId);
GL20.glAttachShader(pId, fsId);
// Bind shader data to vbo attribute list
// GL20.glBindAttribLocation(pId, 0, "vert_in");
// GL20.glBindAttribLocation(pId, 1, "col_in");
// GL20.glBindAttribLocation(pId, 2, "tex0_in");
// GL20.glBindAttribLocation(pId, 3, "norm_in");
// Test Shader
GL20.glBindAttribLocation(pId, 0, "in_Position");
GL20.glBindAttribLocation(pId, 1, "in_Color");
GL20.glBindAttribLocation(pId, 2, "in_TextureCoord");
GL20.glLinkProgram(pId);
GL20.glValidateProgram(pId);
}
private void setupSphere() {
Model sphere = null;
try {
sphere = OBJLoader.loadModel(new File("sphere.obj"));
} catch (IOException e) {
e.printStackTrace();
Display.destroy();
System.exit(1);
}
kugelBuff = GLDrawHelper.directFloatBuffer(sphere.getVVVNNNTT());
indexBuff = GLDrawHelper.directFloatBuffer(sphere.getVertIndices());
kugelVertCount = sphere.getVertCount();
// Create a new Vertex Array Object in memory and select it (bind)
vaoId = GL30.glGenVertexArrays();
GL30.glBindVertexArray(vaoId);
// Create a new Vertex Buffer Object in memory and select it (bind)
vboId = GL15.glGenBuffers();
GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, vboId);
GL15.glBufferData(GL15.GL_ARRAY_BUFFER, kugelBuff, GL15.GL_STATIC_DRAW);
// Attribute Pointer - list id, size, type, normalize, sprite, offset
GL20.glVertexAttribPointer(0, 3, GL11.GL_FLOAT, false, 8*4, 0); // Vertex
// GL20.glVertexAttribPointer(1, 3, GL11.GL_FLOAT, false, 3, 0); // Color
GL20.glVertexAttribPointer(2, 2, GL11.GL_FLOAT, false, 8*4, 6*4); // UV Tex
// GL20.glVertexAttribPointer(3, 3, GL11.GL_FLOAT, false, 8*4, 3*4); // Normals
GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);
// Deselect (bind to 0) the VAO
GL30.glBindVertexArray(0);
// Create a new VBO for the indices and select it (bind) - INDICES
vboiID = GL15.glGenBuffers();
GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, vboiID);
GL15.glBufferData(GL15.GL_ELEMENT_ARRAY_BUFFER, indexBuff, GL15.GL_STATIC_DRAW);
GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, 0);
}
private void update() {
// limit framerate
// Display.sync(ticksPerSecond);
// get time
time = getTime();
diffTime = (time - lastTime)/1000.0f;
lastTime = time;
// Distance mouse has been moved
dx = Mouse.getDX();
dy = Mouse.getDY();
// toggle wireframe
if(Keyboard.isKeyDown(Keyboard.KEY_SPACE)) {
if (time - lastKeySpace > 100) {
fillMode = fillMode == GL_FILL ? GL_LINE : GL_FILL;
glPolygonMode(GL_FRONT_AND_BACK, fillMode);
}
lastKeySpace = time;
}
// mouse control
camera.yaw(dx * mouseSensitivity);
camera.pitch(dy * mouseSensitivity);
// WASD control
if (Keyboard.isKeyDown(Keyboard.KEY_W)) {
camera.walkForward(movementSpeed * diffTime);
}
if (Keyboard.isKeyDown(Keyboard.KEY_S)) {
camera.walkBackwards(movementSpeed * diffTime);
}
if (Keyboard.isKeyDown(Keyboard.KEY_A)) {
camera.strafeLeft(movementSpeed * diffTime);
}
if (Keyboard.isKeyDown(Keyboard.KEY_D)) {
camera.strafeRight(movementSpeed * diffTime);
}
}
private boolean exit() {
return Display.isCloseRequested() || Keyboard.isKeyDown(Keyboard.KEY_ESCAPE);
}
// runner is finished, clean up
private void fini() {
// glDisable(GL_DEPTH_BITS);
// Delete all textures
textureIDs.stream().forEach(GL11::glDeleteTextures);
// Delete the shaders
GL20.glUseProgram(0);
GL20.glDetachShader(pId, vsId);
GL20.glDetachShader(pId, fsId);
GL20.glDeleteShader(vsId);
GL20.glDeleteShader(fsId);
GL20.glDeleteProgram(pId);
// Select the VAO
GL30.glBindVertexArray(vaoId);
// Disable the VBO index from the VAO attributes list
GL20.glDisableVertexAttribArray(0);
GL20.glDisableVertexAttribArray(1);
// Delete the vertex VBO
GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);
GL15.glDeleteBuffers(vboId);
// Delete the index VBO
// GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, 0);
// GL15.glDeleteBuffers(vboiId);
// Delete the VAO
GL30.glBindVertexArray(0);
GL30.glDeleteVertexArrays(vaoId);
Display.destroy();
}
private void updateFPS() {
long time = getTime();
String title;
if (time - lastFPS > 1000) {
// Display.setTitle("FPS: " + fps);
title = "FPS: " + fps + " || avg time per frame: " + (avgTime != 0 ? avgTime/1000f : "-/-") + " ms";
Display.setTitle(title);
fps = 0;
lastFPS += 1000;
}
fps++;
// Frame Count over 1000
if (frameCounter == 1000) {
avgTime = time - frameCounterTime;
// System.out.println("Time for 1000 frames: " + avgTime + " ms.");
frameCounter = 0;
frameCounterTime = time;
}
frameCounter++;
}
private long getTime() {
return (Sys.getTime() * 1000 / Sys.getTimerResolution());
}
private void draw() {
GL11.glClear(GL11.GL_COLOR_BUFFER_BIT);
GL20.glUseProgram(pId);
// Bind the texture
GL13.glActiveTexture(GL13.GL_TEXTURE0);
GL11.glBindTexture(GL11.GL_TEXTURE_2D, textureIDs.get(0));
// Bind to the VAO that has all the information about the vertices
GL30.glBindVertexArray(vaoId);
GL20.glEnableVertexAttribArray(0);
// GL20.glEnableVertexAttribArray(1);
GL20.glEnableVertexAttribArray(2);
GL20.glEnableVertexAttribArray(3);
// Bind to the index VBO that has all the information about the order of the vertices
GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, vboiID);
// Draw the vertices
GL11.glDrawElements(GL11.GL_TRIANGLES, kugelVertCount, GL11.GL_UNSIGNED_BYTE, 0);
// Put everything back to default (deselect)
GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, 0);
GL20.glDisableVertexAttribArray(0);
// GL20.glDisableVertexAttribArray(1);
GL20.glDisableVertexAttribArray(2);
GL20.glDisableVertexAttribArray(3);
GL30.glBindVertexArray(0);
GL20.glUseProgram(0);
Display.update();
}
private static String[] getTextureFiles(String directory) {
File pathfile = new File(directory);
File[] files = pathfile.listFiles( (File dir, String name) ->
name.endsWith(".jpg") || name.endsWith(".png")
);
return Arrays.stream(files).map(File::toString).toArray(String[]::new);
}
public static void main(String[] args) {
new Mobile();
}
}
Sorry for the code mess. Maybe this is better readable. https://codeshare.io/1SEQK
回答1:
Don't be desperate, amaridev.
When you can't get nothing rendered you have in general two option:
start from something basic and working (like this hello triangle from mine, it's jogl but you can port it to lwjgl very easily) and build on top of that
debug your application step by step
In case you decide for the second one, you may want to disable first and lighting, any matrix multiplication and any texturing:
- check your rendering targets setup by testing if you see the clear color you set
- check if
glViewportand the fragment shader work by running an hardcoded vertex shader with:
gl_Position = vec4(4.0 * float(gl_VertexID % 2) - 1.0, 4.0 * float(gl_VertexID / 2) - 1.0, 0.0, 1.0);
like here, no matrices and a simple
glDrawArrays(GL_TRIANGLES, 3, 0);
you may want also to hardcode the color output
check if you are reading valid vertex attributes, by outputting each of them in turn to the color fragment shader
out Block { vec4 color } outBlock; ... outBlock.color = position;
in Block { vec4 color; } inBlock; outputColor = inBlock.color;
enable matrix multiplication and pass a simple hardcoded triangle to check if any matrix (first proj, then view and finally also model) works as expected
start fetching from your real sphere geometry
start fetching color
enable again texturing and start fetching texture coordinates again
output light and materials values to output color and then enable them back as well
来源：https://stackoverflow.com/questions/38020841/basic-opengl-3-2-setup-with-lwjgl-object-not-rendered