Fix mat4:lookAt;

src/api/l_vectors.c

@@ -1640,7 +1640,7 @@ static int l_lovrMat4LookAt(lua_State* L) {
   mat4 m = luax_checkvector(L, 1, V_MAT4, NULL);
   vec3 from = luax_checkvector(L, 2, V_VEC3, NULL);
   vec3 to = luax_checkvector(L, 3, V_VEC3, NULL);
-  vec3 up = lua_isnoneornil(L, 4) ? (float[4]) { 0.f, 1.f, 0.f } : luax_checkvector(L, 3, V_VEC3, NULL);
+  vec3 up = lua_isnoneornil(L, 4) ? (float[4]) { 0.f, 1.f, 0.f } : luax_checkvector(L, 4, V_VEC3, NULL);
   mat4_lookAt(m, from, to, up);
   lua_settop(L, 1);
   return 1;

src/core/maf.h

@@ -611,27 +611,27 @@ MAF mat4 mat4_fov(mat4 m, float left, float right, float up, float down, float c
 }
 
 MAF mat4 mat4_lookAt(mat4 m, vec3 from, vec3 to, vec3 up) {
-  float z[4];
   float x[4];
   float y[4];
-  vec3_sub(vec3_init(z, to), from);
+  float z[4];
+  vec3_normalize(vec3_sub(vec3_init(z, from), to));
   vec3_normalize(vec3_cross(vec3_init(x, up), z));
   vec3_cross(vec3_init(y, z), x);
   m[0] = x[0];
-  m[1] = y[0];
-  m[2] = z[0];
+  m[1] = x[1];
+  m[2] = x[2];
   m[3] = 0.f;
-  m[4] = x[1];
+  m[4] = y[0];
   m[5] = y[1];
-  m[6] = z[1];
+  m[6] = y[2];
   m[7] = 0.f;
-  m[8] = x[2];
-  m[9] = y[2];
+  m[8] = z[0];
+  m[9] = z[1];
   m[10] = z[2];
   m[11] = 0.f;
-  m[12] = 0.f;
-  m[13] = 0.f;
-  m[14] = 0.f;
+  m[12] = from[0];
+  m[13] = from[1];
+  m[14] = from[2];
   m[15] = 1.f;
   return m;
 }