Initial commit.

escalator.cpp

@@ -0,0 +1,50 @@
+// -*- C++ -*-
+
+#include "escalator.h"
+#include "material.h"
+#include "model.h"
+#include "physics/particle.h"
+#include "physics/shape.h"
+#include "physics/vector.h"
+
+using namespace mbostock;
+
+Escalator::Escalator(const Vector& min, const Vector& max, const Vector& v)
+    : box_(min, max), velocity_(v * ParticleSimulator::timeStep()),
+      model_(box_) {
+  model_.setTexOrientation((fabsf(v.x) > fabsf(v.z))
+      ? ((v.x > 0) ? AxisAlignedBoxModel::POSITIVE_X
+                   : AxisAlignedBoxModel::NEGATIVE_X)
+      : ((v.z > 0) ? AxisAlignedBoxModel::POSITIVE_Z
+                   : AxisAlignedBoxModel::NEGATIVE_Z));
+}
+
+Model& Escalator::model() {
+  return model_;
+}
+
+const Shape& Escalator::shape() const {
+  return box_;
+}
+
+void Escalator::step(const ParticleSimulator& s) {
+  offset_.x = fmodf(offset_.x + velocity_.x, 1.f);
+  offset_.z = fmodf(offset_.z + velocity_.z, 1.f);
+  model_.setTexOffset(-offset_.x, -offset_.z);
+}
+
+Vector Escalator::velocity(const Vector& x) const {
+  return velocity_;
+}
+
+void Escalator::setMaterial(const Material& m) {
+  model_.setMaterial(m);
+}
+
+void Escalator::setTopMaterial(const Material& m) {
+  model_.setTopMaterial(m);
+}
+
+float Escalator::slip() const {
+  return model_.material().slip();
+}