fistcommit

src/part3D/engine.c

@@ -0,0 +1,56 @@
+#ifndef ENGINE_H
+#define ENGINE_H
+
+#include "defines.h"
+
+#define f_to_int(a)    ((a) >> 16)
+#define int_to_f(a)    ((a) << 16)
+// #define f_mul(a, b)    ((fixed)(((int64_t)(a) * (b)) >> 16))
+inline fixed f_mul(fixed a, fixed b) { return (fixed)(((int64_t)a * b) >> 16); }
+inline fixed f_div(fixed a, fixed b) {
+	if (b == 0) return 0; // Évite la division par zéro
+	return (fixed)(((int64_t)a << 16) / b);
+}
+
+// Matrice 3x3 pour la rotation des normales et des sommets
+typedef struct { fixed m[3][3]; } Matrix3;
+
+void mat3_identity(Matrix3 *mat) {
+	memset(mat, 0, sizeof(Matrix3));
+	mat->m[0][0] = mat->m[1][1] = mat->m[2][2] = int_to_f(1);
+}
+
+static fixed sintab[360], costab[360], inv_table[321];
+
+void init_engine_math() {
+	for (int i = 0; i < 360; i++) {
+		double r = (double)i * 3.14159265 / 180.0;
+		sintab[i] = (fixed)(sin(r) * 65536.0);
+		costab[i] = (fixed)(cos(r) * 65536.0);
+	}
+	inv_table[0] = 0;
+	for (int i = 1; i <= 320; i++) inv_table[i] = (int_to_f(1) / i);
+}
+
+typedef struct { fixed x, y, z; } Vector3;
+
+typedef struct { int a, b, c; uint8_t color; uint8_t force_wire; } Face;
+typedef struct { int x, y; fixed z; int intensity; } Point2D;
+
+typedef struct {
+	Vector3 *verts;
+	Vector3 *v_normals;
+	Face *faces;
+	int num_verts, num_faces;
+} Mesh;
+
+// Normalisation pour le Gouraud (à la création uniquement)
+void normalize(Vector3 *v) {
+	double dx = (double)v->x, dy = (double)v->y, dz = (double)v->z;
+	double d = sqrt(dx*dx + dy*dy + dz*dz);
+	if (d > 0) {
+		v->x = (fixed)((dx/d)*65536.0); v->y = (fixed)((dy/d)*65536.0); v->z = (fixed)((dz/d)*65536.0);
+	}
+}
+
+#endif