Projection.cpp

#include "Projection.h"

float* PerspectiveProject(float tesseractVertices[64], float cameraPos[4], float fovScale, float scale[2], int offset[2]) {
	float* projectedPoints = new float[32];

	float xc, yc, zc, wc, x, y, z, w, temp, x3d, y3d, z3d, x2d, y2d;
	xc = cameraPos[0];
	yc = cameraPos[1];
	zc = cameraPos[2];
	wc = cameraPos[3];

	for (int i = 0; i < 64; i += 4) {
		x = tesseractVertices[i];
		y = tesseractVertices[i + 1];
		z = tesseractVertices[i + 2];
		w = tesseractVertices[i + 3];

		// 4D to 3D perspective projection
		// Ensure w != wc to avoid division by zero
		if (w != wc) {
			temp = w - wc;
			x3d = (x - xc) / temp;
			y3d = (y - yc) / temp;
			z3d = (z - zc) / temp;
		}
		else {
			x3d = x - xc;
			y3d = y - yc;
			z3d = z - zc;
		}

		// 3D to 2D perspective projection
		if (z3d + fovScale) {
			x2d = (x3d * fovScale) / (z3d + fovScale);
			y2d = (y3d * fovScale) / (z3d + fovScale);
		}
		else {
			x2d = x3d;
			y2d = y3d;
		}
		int projectIndex = i / 2;
		projectedPoints[projectIndex] = x2d * scale[0] + offset[0];
		projectedPoints[projectIndex + 1] = y2d * scale[1] + offset[1];
	}

	return projectedPoints;
}