Deep Line-by-Line Analysis: Fisheye Correction

Click on any line of code to see its detailed explanation and visualization!

Move your mouse in the visualization area to see real-time calculations.

Function 1: use_distance(float x, float y)

Simple Euclidean distance calculator using Pythagorean theorem

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float use_distance(float x, float y) {
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    return (sqrt(x * x + y * y));
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}
Function 2: use_fixed_dist(float x2, float y2, t_cub *game)

Fisheye correction function - projects 3D distance onto 2D viewing plane

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float use_fixed_dist(float x2, float y2, t_cub *game) {
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    float delta_x;
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    float delta_y;
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    float angle;
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    float fix_dist;
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    delta_x = x2 - game->player.x;
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    delta_y = y2 - game->player.y;
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    angle = atan2(delta_y, delta_x) - game->player.angle;
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    fix_dist = use_distance(delta_x, delta_y) * cos(angle);
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    return (fix_dist);
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}

2D Top View

Calculation Steps

Click on a line of code to see detailed explanation

This interactive demo shows each step of the fisheye correction algorithm. The math behind preventing visual distortion in raycasting engines.

Mouse Position: (150, 100)
Player Position: (175, 175)
Player Angle: -90°