opt wip

examples/projects/CMakeLists.txt

@@ -3,6 +3,7 @@ add_subdirectory(Crane3R)
 add_subdirectory(InvertedPendulum)
 add_subdirectory(MapView)
 add_subdirectory(MotorControl)
+add_subdirectory(Optimization)
 add_subdirectory(Pathfinding)
 add_subdirectory(Snake)
 add_subdirectory(Youbot)

examples/projects/Optimization/CMakeLists.txt

@@ -0,0 +1,2 @@
+
+add_example(NAME optimization SOURCES main.cpp)

examples/projects/Optimization/main.cpp

@@ -0,0 +1,75 @@
+
+#include "threepp/math/Lut.hpp"
+#include "threepp/math/MathUtils.hpp"
+#include "threepp/threepp.hpp"
+
+
+using namespace threepp;
+
+namespace {
+
+    void rosenbrock(PlaneGeometry& geometry, float a = 1, float b = 100) {
+
+        auto pos = geometry.getAttribute<float>("position");
+        auto& vertices = pos->array();
+
+        std::vector<float> yValues;
+        yValues.reserve(vertices.size() / 3);
+        for (auto i = 0; i < vertices.size(); i += 3) {
+
+            float x = vertices[i];
+            float z = vertices[i + 2];
+            float y = ((a - x) * (a - x)) + b * ((z - (x * x)) * (z - (x * x)));
+
+            vertices[i + 1] = y;
+            yValues.emplace_back(y);
+        }
+
+        Lut::addColorMap("rainbow", {{0.f, 0x0000ff}, {0.01f, 0x00ffff}, {0.1f, 0xffff00}, {1.f, 0xff0000}});
+        Lut lut("rainbow");
+        auto colors = std::vector<float>(vertices.size());
+        auto minMax = std::minmax_element(yValues.begin(), yValues.end());
+        for (auto i = 0; i < vertices.size(); i += 3) {
+
+            float y = vertices[i + 1];
+
+            Color c = lut.getColor(math::mapLinear(y, *minMax.first, *minMax.second, 0, 1));
+            c.toArray(colors, i);
+        }
+        geometry.setAttribute("color", FloatBufferAttribute::create(colors, 3));
+        geometry.scale(1, 0.001, 1);
+
+        pos->needsUpdate();
+    }
+
+}// namespace
+
+int main() {
+
+    Canvas canvas("Optimization");
+    GLRenderer renderer(canvas.size());
+
+    Scene scene;
+    scene.background = Color::aliceblue;
+
+    PerspectiveCamera camera(60, canvas.aspect());
+    camera.position.z = 10;
+
+    OrbitControls controls(camera, canvas);
+
+    auto planeGeometry = PlaneGeometry::create(4, 4, 100, 100);
+    auto planeGeometry2 = PlaneGeometry::create(4, 4, 20, 20);
+    planeGeometry->applyMatrix4(Matrix4().makeRotationX(-math::PI / 2));
+    planeGeometry2->applyMatrix4(Matrix4().makeRotationX(-math::PI / 2));
+    rosenbrock(*planeGeometry);
+    rosenbrock(*planeGeometry2);
+    auto plane = Mesh::create(planeGeometry, MeshBasicMaterial::create({{"wireframe", false}, {"vertexColors", true}}));
+    auto wireframe = Mesh::create(planeGeometry2, MeshBasicMaterial::create({{"wireframe", true}}));
+
+    plane->add(wireframe);
+    scene.add(plane);
+
+    canvas.animate([&] {
+        renderer.render(scene, camera);
+    });
+}