From 56a92d302f62e753f895df769099ebd3f115b94a Mon Sep 17 00:00:00 2001
From: Gent <gentsemaj@live.com>
Date: Sat, 26 Sep 2020 18:45:19 -0400
Subject: [PATCH] Add curve parameter to lerp

---
 src/TableData.cpp        | 12 ++++++++++--
 src/TransportManager.cpp | 12 ++++++++----
 src/TransportManager.hpp |  1 +
 3 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/src/TableData.cpp b/src/TableData.cpp
index 13993f3..c820f9f 100644
--- a/src/TableData.cpp
+++ b/src/TableData.cpp
@@ -239,10 +239,11 @@ void TableData::loadPaths(int* nextId) {
         std::cout << "[INFO] Loaded " << TransportManager::SkywayPaths.size() << " skyway paths" << std::endl;
 
         // slider circuit
+        int sliders = 0;
         nlohmann::json pathDataSlider = pathData["slider"];
         for (nlohmann::json::iterator _sliderPoint = pathDataSlider.begin(); _sliderPoint != pathDataSlider.end(); _sliderPoint++) {
             auto sliderPoint = _sliderPoint.value();
-            if (sliderPoint["stop"]) { // check if this point in the circuit is a stop
+            if (sliderPoint["stop"] && sliders % 2 == 0) { // check if this point in the circuit is a stop
                 // spawn a slider
                 std::cout << "bus ID was " << *nextId << std::endl;
                 BaseNPC* slider = new BaseNPC(sliderPoint["iX"], sliderPoint["iY"], sliderPoint["iZ"], 1, (*nextId)++, NPC_BUS);
@@ -250,6 +251,7 @@ void TableData::loadPaths(int* nextId) {
                 NPCManager::updateNPCPosition(slider->appearanceData.iNPC_ID, slider->appearanceData.iX, slider->appearanceData.iY, slider->appearanceData.iZ);
                 // set slider path to a rotation of the circuit
                 constructPathSlider(pathDataSlider, 0, slider->appearanceData.iNPC_ID);
+                sliders++;
             }
         }
 
@@ -300,7 +302,13 @@ void TableData::constructPathSlider(nlohmann::json points, int rotations, int sl
         for (int i = 0; i < stopTime + 1; i++) // repeat point if it's a stop
             route.push(from); // add point A to the queue
         WarpLocation to = { point["iX"] , point["iY"] , point["iZ"] }; // point B coords
-        TransportManager::lerp(&route, from, to, SLIDER_SPEED); // lerp from A to B (arbitrary speed)
+        float curve = 1;
+        if (stopTime > 0) { // point A is a stop
+            curve = 2.0f;
+        } else if (point["stop"]) { // point B is a stop
+            curve = 0.35f;
+        }
+        TransportManager::lerp(&route, from, to, SLIDER_SPEED, curve); // lerp from A to B (arbitrary speed)
         from = to; // update point A
         stopTime = point["stop"] ? SLIDER_STOP_TICKS : 0;
     }
diff --git a/src/TransportManager.cpp b/src/TransportManager.cpp
index 64f959e..dc8409d 100644
--- a/src/TransportManager.cpp
+++ b/src/TransportManager.cpp
@@ -311,17 +311,21 @@ void TransportManager::stepNPCPathing() {
 /*
  * Linearly interpolate between two points and insert the results into a queue.
  */
-void TransportManager::lerp(std::queue<WarpLocation>* queue, WarpLocation start, WarpLocation end, int gapSize) {
+void TransportManager::lerp(std::queue<WarpLocation>* queue, WarpLocation start, WarpLocation end, int gapSize, float curve) {
     int dXY = hypot(end.x - start.x, end.y - start.y); // XY plane distance
     int distanceBetween = hypot(dXY, end.z - start.z); // total distance
-    int lerps = distanceBetween / gapSize; // integer division to ensure a whole number of in-between points
-    for (int i = 0; i < lerps; i++) {
+    int lerps = distanceBetween / gapSize; // number of intermediate points to add
+    for (int i = 1; i <= lerps; i++) {
         WarpLocation lerp;
         // lerp math
-        float frac = (i + 1) * 1.0f / (lerps + 1);
+        //float frac = i / (lerps + 1);
+        float frac = powf(i, curve) / powf(lerps + 1, curve);
         lerp.x = (start.x * (1.0f - frac)) + (end.x * frac);
         lerp.y = (start.y * (1.0f - frac)) + (end.y * frac);
         lerp.z = (start.z * (1.0f - frac)) + (end.z * frac);
         queue->push(lerp); // add lerp'd point
     }
 }
+void TransportManager::lerp(std::queue<WarpLocation>* queue, WarpLocation start, WarpLocation end, int gapSize) {
+    lerp(queue, start, end, gapSize, 1);
+}
diff --git a/src/TransportManager.hpp b/src/TransportManager.hpp
index d905455..7df3825 100644
--- a/src/TransportManager.hpp
+++ b/src/TransportManager.hpp
@@ -34,5 +34,6 @@ namespace TransportManager {
     void stepNPCPathing();
     void stepSkywaySystem();
 
+    void lerp(std::queue<WarpLocation>*, WarpLocation, WarpLocation, int, float);
     void lerp(std::queue<WarpLocation>*, WarpLocation, WarpLocation, int);
 }