diff --git a/selfdrive/common/modeldata.h b/selfdrive/common/modeldata.h
index 9a9414cfa3..8d91f7be10 100644
--- a/selfdrive/common/modeldata.h
+++ b/selfdrive/common/modeldata.h
@@ -10,33 +10,19 @@ const int LON_MPC_N = 32;
 const float MIN_DRAW_DISTANCE = 10.0;
 const float MAX_DRAW_DISTANCE = 100.0;
 
-template<typename T_SRC, typename  T_DST, size_t size>
-const std::array<T_DST, size> convert_array_to_type(const std::array<T_SRC, size> &src) {
-  std::array<T_DST, size> dst = {};
-  for (int i=0; i<size; i++) {
-    dst[i] = src[i];
+template <typename T, size_t size>
+constexpr std::array<T, size> build_idxs(float max_val) {
+  std::array<T, size> result{};
+  for (int i = 0; i < size; ++i) {
+    result[i] = max_val * ((i / (double)(size - 1)) * (i / (double)(size - 1)));
   }
-  return dst;
+  return result;
 }
 
-const std::array<double, TRAJECTORY_SIZE> T_IDXS = {
-        0.        ,  0.00976562,  0.0390625 ,  0.08789062,  0.15625   ,
-        0.24414062,  0.3515625 ,  0.47851562,  0.625     ,  0.79101562,
-        0.9765625 ,  1.18164062,  1.40625   ,  1.65039062,  1.9140625 ,
-        2.19726562,  2.5       ,  2.82226562,  3.1640625 ,  3.52539062,
-        3.90625   ,  4.30664062,  4.7265625 ,  5.16601562,  5.625     ,
-        6.10351562,  6.6015625 ,  7.11914062,  7.65625   ,  8.21289062,
-        8.7890625 ,  9.38476562, 10.};
-const auto T_IDXS_FLOAT = convert_array_to_type<double, float, TRAJECTORY_SIZE>(T_IDXS);
-
-const std::array<double, TRAJECTORY_SIZE> X_IDXS = {
-         0.    ,   0.1875,   0.75  ,   1.6875,   3.    ,   4.6875,
-         6.75  ,   9.1875,  12.    ,  15.1875,  18.75  ,  22.6875,
-        27.    ,  31.6875,  36.75  ,  42.1875,  48.    ,  54.1875,
-        60.75  ,  67.6875,  75.    ,  82.6875,  90.75  ,  99.1875,
-       108.    , 117.1875, 126.75  , 136.6875, 147.    , 157.6875,
-       168.75  , 180.1875, 192.};
-const auto X_IDXS_FLOAT = convert_array_to_type<double, float, TRAJECTORY_SIZE>(X_IDXS);
+constexpr auto T_IDXS = build_idxs<double, TRAJECTORY_SIZE>(10.0);
+constexpr auto T_IDXS_FLOAT = build_idxs<float, TRAJECTORY_SIZE>(10.0);
+constexpr auto X_IDXS = build_idxs<double, TRAJECTORY_SIZE>(192.0);
+constexpr auto X_IDXS_FLOAT = build_idxs<float, TRAJECTORY_SIZE>(192.0);
 
 const int TICI_CAM_WIDTH = 1928;