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The near plane clips at exactly the value I set just fine but instead of clipping at 1000 the far plane clips at 1.

Here is the code for the projection matrix:

public static Matrix4f perspective(Matrix4f dest, float fov, float aspectRatio, float near, float far) {
    if (dest == null)
        dest = new Matrix4f();

    float tanHalfFOV = (float) Math.tan(fov / 2);
    float range = near - far;

    dest.m00 = 1.0f / (tanHalfFOV * aspectRatio);
    dest.m10 = 0;
    dest.m20 = 0;
    dest.m30 = 0;
    dest.m01 = 0;
    dest.m11 = 1.0f / tanHalfFOV;
    dest.m21 = 0;
    dest.m31 = 0;
    dest.m02 = 0;
    dest.m12 = 0;
    dest.m22 = (-near - far) / range;
    dest.m32 = 2 * far * near / range;
    dest.m03 = 0;
    dest.m13 = 0;
    dest.m23 = 1;
    dest.m33 = 0;

    return dest;
}

The near plane is 0.1 and the far plane is supposed to be 1000.

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2 Answers 2

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Your whole matrix is incorrect. For example, this is one of the ways it should look like:

prrojection matrix

So, in code:

dest.m00 = 1.0f / (tanHalfFOV * aspectRatio);
dest.m10 = 0;
dest.m20 = 0;
dest.m30 = 0;
dest.m01 = 0;
dest.m11 = 1.0f / tanHalfFOV;
dest.m21 = 0;
dest.m31 = 0;
dest.m02 = 0;
dest.m12 = 0;
dest.m22 = -(far + near) / range;
dest.m32 = -2 * far * near / range;
dest.m03 = 0;
dest.m13 = 0;
dest.m23 = -1;
dest.m33 = 0;

And you calculate range the wrong way, it needs to be far - near, not near - far.

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  • \$\begingroup\$ You were a bit rush when blamed the original matrix 'wrong'. It is correct. You can find it, for example here. \$\endgroup\$
    – Grief
    Jun 3, 2017 at 22:11
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As far as I can tell by comparing to GLM perspective matrix implementation, your range is computed negative and you are missing some negative signs. Below are the corrections.

float range = far - near;
...
dest.m32 = - 2 * far * near / range;
dest.m23 = - 1;

Check it out on their git. I am not sure just which matrix you need, this answer is for the RH one. Check the link for other implementations.

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  • \$\begingroup\$ Wiith this nothing shows up at all. \$\endgroup\$ Mar 24, 2016 at 3:07
  • 1
    \$\begingroup\$ @minecraftwarlock perhaps a sign is wrong somewhere or the camera is positioned incorrectly \$\endgroup\$
    – Bikush
    Mar 24, 2016 at 13:52

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