feat: added the ability to render whole model

polygon.hpp

@@ -4,25 +4,48 @@
 #include "fastmath.hpp"
 struct polygon {
 
-    const vec3 points[3];
+    vec3 points[3];
+    vec3 delta[3];
+    bool skip = false;
 
     polygon(const vec3 &v1, const vec3 &v2, const vec3 &v3)
         : points{v1, v2, v3} {}
+    polygon() : points{} {}
+
+    void calcDelta() {
 
-    bool contains(const vec3 &p) {
         for (int i = 0; i < 3; i++) {
             int n = (i + 1) % 3;
 
             vec3 d = points[n] - points[i];
-            d = vec3(d.y(), -d.x(), d.z());
+            delta[i] = vec3(d.y(), -d.x(), d.z());
+            if (delta[i].isSmall()) {
+                skip = true;
+                return;
+            }
+        }
+    }
+
+    bool contains(const vec3 &p) {
+        if (skip)
+            return false;
+        for (int i = 0; i < 3; i++) {
+            int n = (i + 1) % 3;
 
             vec3 s = p - points[n];
-
-            if (s * d < decimal(0.0))
+            if (s.isSmall())
+                return false;
+            if (s * delta[i] <= decimal(0.0))
                 return false;
         }
         return true;
     }
+    friend std::ostream &operator<<(std::ostream &os, const polygon &p) {
+        for (int i = 0; i < 3; i++) {
+            os << p.points[i];
+        }
+        return os;
+    }
 };
 
 #endif