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View Matrix in LWJGL 3 not showing right

My view matrix in my camera class is setup up correctly, with the rotation and negative translation, but it moves the camera somewhere else, and I can't seem to find my model. Rotation and translation matrices are working because translations are working and my model and projection matrices are also working, but when I add the view matrix, it only shows parts of the model. By the way, made my own matrix math classes.

Matrix Math Class

package engine.maths;

public class Matrix4f
private float matrix;

public Matrix4f()
matrix = new float[4][4];


public Matrix4f identity()
matrix[0][0] = 1; matrix[0][1] = 0; matrix[0][2] = 0; matrix[0][3] = 0;
matrix[1][0] = 0; matrix[1][1] = 1; matrix[1][2] = 0; matrix[1][3] = 0;
matrix[2][0] = 0; matrix[2][1] = 0; matrix[2][2] = 1; matrix[2][3] = 0;
matrix[3][0] = 0; matrix[3][1] = 0; matrix[3][2] = 0; matrix[3][3] = 1;

return this;


public Matrix4f translate(Vector3f vector)
matrix[0][0] = 1; matrix[0][1] = 0; matrix[0][2] = 0; matrix[0][3] = vector.getX();
matrix[1][0] = 0; matrix[1][1] = 1; matrix[1][2] = 0; matrix[1][3] = vector.getY();
matrix[2][0] = 0; matrix[2][1] = 0; matrix[2][2] = 1; matrix[2][3] = vector.getZ();
matrix[3][0] = 0; matrix[3][1] = 0; matrix[3][2] = 0; matrix[3][3] = 1;

return this;


public Matrix4f rotate(Vector3f vector)
Matrix4f rotateX = new Matrix4f();
Matrix4f rotateY = new Matrix4f();
Matrix4f rotateZ = new Matrix4f();

Vector3f rotatedVector = new Vector3f((float) Math.toRadians(vector.getX()), (float) Math.toRadians(vector.getY()), (float) Math.toRadians(vector.getZ()));

rotateZ.matrix[0][0] = (float)Math.cos(rotatedVector.getZ()); rotateZ.matrix[0][1] = -(float)Math.sin(rotatedVector.getZ()); rotateZ.matrix[0][2] = 0; rotateZ.matrix[0][3] = 0;
rotateZ.matrix[1][0] = (float)Math.sin(rotatedVector.getZ()); rotateZ.matrix[1][1] = (float)Math.cos(rotatedVector.getZ()); rotateZ.matrix[1][2] = 0; rotateZ.matrix[1][3] = 0;
rotateZ.matrix[2][0] = 0; rotateZ.matrix[2][1] = 0; rotateZ.matrix[2][2] = 1; rotateZ.matrix[2][3] = 0;
rotateZ.matrix[3][0] = 0; rotateZ.matrix[3][1] = 0; rotateZ.matrix[3][2] = 0; rotateZ.matrix[3][3] = 1;

rotateX.matrix[0][0] = 1; rotateX.matrix[0][1] = 0; rotateX.matrix[0][2] = 0; rotateX.matrix[0][3] = 0;
rotateX.matrix[1][0] = 0; rotateX.matrix[1][1] = (float)Math.cos(rotatedVector.getX()); rotateX.matrix[1][2] = -(float)Math.sin(rotatedVector.getX()); rotateX.matrix[1][3] = 0;
rotateX.matrix[2][0] = 0; rotateX.matrix[2][1] = (float)Math.sin(rotatedVector.getX()); rotateX.matrix[2][2] = (float)Math.cos(rotatedVector.getX()); rotateX.matrix[2][3] = 0;
rotateX.matrix[3][0] = 0; rotateX.matrix[3][1] = 0; rotateX.matrix[3][2] = 0; rotateX.matrix[3][3] = 1;

rotateY.matrix[0][0] = (float)Math.cos(rotatedVector.getY()); rotateY.matrix[0][1] = 0; rotateY.matrix[0][2] = -(float)Math.sin(rotatedVector.getY()); rotateY.matrix[0][3] = 0;
rotateY.matrix[1][0] = 0; rotateY.matrix[1][1] = 1; rotateY.matrix[1][2] = 0; rotateY.matrix[1][3] = 0;
rotateY.matrix[2][0] = (float)Math.sin(rotatedVector.getY()); rotateY.matrix[2][1] = 0; rotateY.matrix[2][2] = (float)Math.cos(rotatedVector.getY()); rotateY.matrix[2][3] = 0;
rotateY.matrix[3][0] = 0; rotateY.matrix[3][1] = 0; rotateY.matrix[3][2] = 0; rotateY.matrix[3][3] = 1;

matrix = rotateZ.mul(rotateY.mul(rotateX)).getMatrix();

return this;


public Matrix4f scale(Vector3f vector)
matrix[0][0] = vector.getX(); matrix[0][1] = 0; matrix[0][2] = 0; matrix[0][3] = 0;
matrix[1][0] = 0; matrix[1][1] = vector.getY(); matrix[1][2] = 0; matrix[1][3] = 0;
matrix[2][0] = 0; matrix[2][1] = 0; matrix[2][2] = vector.getZ(); matrix[2][3] = 0;
matrix[3][0] = 0; matrix[3][1] = 0; matrix[3][2] = 0; matrix[3][3] = 1;

return this;


public Matrix4f projection(float fov, float aspectRatio, float zNear, float zFar)
float tanHalfFOV = (float) Math.tan(Math.toRadians(fov / 2));
float zRange = zNear - zFar;

matrix[0][0] = 1.0f / (tanHalfFOV * aspectRatio); matrix[0][1] = 0; matrix[0][2] = 0; matrix[0][3] = 0;
matrix[1][0] = 0; matrix[1][1] = 1.0f / tanHalfFOV; matrix[1][2] = 0; matrix[1][3] = 0;
matrix[2][0] = 0; matrix[2][1] = 0; matrix[2][2] = (-zNear - zFar) / zRange; matrix[2][3] = 2 * zFar * zNear / zRange;
matrix[3][0] = 0; matrix[3][1] = 0; matrix[3][2] = 1; matrix[3][3] = 0;

return this;


public Matrix4f mul(Matrix4f m)
Matrix4f result = new Matrix4f();

for (int i = 0; i < 4; i++)
for (int j = 0; j < 4; j++)
result.set(i, j, matrix[i][0] * m.get(0, j) +
matrix[i][1] * m.get(1, j) +
matrix[i][2] * m.get(2, j) +
matrix[i][3] * m.get(3, j));



return result;


public float getMatrix()
return matrix;


public void setMatrix(float matrix)
this.matrix = matrix;


public float get(int x, int y)
return matrix[x][y];


public void set(int x, int y, float value)
matrix[x][y] = value;


public String toString()
String matrix = "";
for (int i = 0; i < 4; i++)
for (int j = 0; j < 4; j++)
matrix += (Float.toString(get(i, j)) + ", ");

matrix += "n";

return matrix + "";




Camera Class

package engine.rendering;

import engine.maths.Matrix4f;
import engine.maths.Vector3f;

public class Camera
private Vector3f position, rotation;
public Camera(Vector3f position, Vector3f rotation)
this.position = position;
this.rotation = rotation;


public Matrix4f getViewMatrix()
Matrix4f rotationMatrix = new Matrix4f().identity().rotate(rotation);
Vector3f negativePosition = new Vector3f(-position.getX(), -position.getY(), -position.getZ());
Matrix4f translationMatrix = new Matrix4f().identity().translate(negativePosition);
return rotationMatrix.mul(translationMatrix);


public void addPosition(float x, float y, float z)
position.add(new Vector3f(x, y, z));


public void addPosition(Vector3f value)
position.add(value);


public void setPosition(float x, float y, float z)
position = new Vector3f(x, y, z);


public void setPosition(Vector3f pos)
position = pos;


public Vector3f getPosition()
return position;


public void addRotation(float x, float y, float z)
rotation.add(new Vector3f(x, y, z));


public void addRotation(Vector3f value)
rotation.add(value);


public void setRotation(float x, float y, float z)
rotation = new Vector3f(x, y, z);


public void setRotation(Vector3f rot)
rotation = rot;


public Vector3f getRotation()
return rotation;




Loading Matrix Class

package engine.shaders;

import engine.maths.Matrix4f;

public class BasicShader extends Shader

private static final String VERTEX_FILE = "src/engine/shaders/basicVertexShader.glsl";
private static final String FRAGMENT_FILE = "src/engine/shaders/basicFragmentShader.glsl";

private int tvpMatrixLocation;

private Matrix4f transformationMatrix = new Matrix4f().identity(), projectionMatrix = new Matrix4f().identity(), viewMatrix = new Matrix4f().identity();

public BasicShader()
super(VERTEX_FILE, FRAGMENT_FILE);


@Override
protected void bindAttributes()
super.bindAttribute(0, "position");
super.bindAttribute(1, "textCoords");


@Override
protected void getAllUniforms()
tvpMatrixLocation = super.getUniform("tvpMatrix");


public void useMatrices()
super.loadMatrixUniform(tvpMatrixLocation, transformationMatrix.mul(projectionMatrix.mul(viewMatrix)));


public void loadTransformationMatrix(Matrix4f matrix)
transformationMatrix = matrix;


public void loadProjectionMatrix(Matrix4f matrix)
projectionMatrix = matrix;


public void loadViewMatrix(Matrix4f matrix)
viewMatrix = matrix;




2 Answers
2

Your projection matrix has a fault: matrix[3][2] = 1 must be -1.

matrix[3][2] = 1

-1

This is due to OpenGL NDC space is special, cross product XxY gives -Z instead of Z.

XxY

-Z

Z

The surprising fact is that all visible objects must have a negative Z-coordinate in view space.

This is not making any sense:

super.loadMatrixUniform(tvpMatrixLocation, transformationMatrix.mul(projectionMatrix.mul(viewMatrix)));


No matter what conventions you use, and which order the mul() method actually multiplies. you either end up with T*P*V, or V*P*T, which both woudln't be correct (for the typical use case of not applying some additional transformation after the projection).

mul()

T*P*V

V*P*T

P*V*T

T*V*P

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