test_map_vs_loop.cpp

// a map used for storing distances between target and mesh points
// the key is a pair made by the target point and mesh point indices
// the value is the distance between those two points
std::map <pair<int,int>, float> distances_map;

for (int t = 0; t < target_points.size(); t++){

    ofPoint random_point = target_points.at(t);

    for (int p = 0; p < plane.getNumVertices(); p++){

        ofPoint mesh_point = ofPoint(plane.getVertex(p));

        float current_distance = ofDist(random_point.x, random_point.y, random_point.z, mesh_point.x, mesh_point.y, mesh_point.z);

        // store this distance in the map so that we can later retrieve it quickly without recomputing it
        pair<int, int> key = std::make_pair(t, p);
        distances_map[key] = current_distance;

        if (current_distance > max_distance) max_distance = current_distance;
    }
}

// 2.2 apply the amplitude to the y axis of the vertex
for (int t = 0; t < target_points.size(); t++){

    ofPoint random_point = target_points.at(t);

    for (int p = 0; p < plane.getNumVertices(); p++){

        ofPoint mesh_point = plane.getVertex(p);

        // get the distance from the map where we stored it
        pair<int, int> key = std::make_pair(t, p);
        float current_distance = distances_map[key];

        // float current_distance = ofDist(random_point.x, random_point.y, random_point.z, mesh_point.x, mesh_point.y, mesh_point.z);
        // amp gets weaker the more distant it is from the point
        float amp_strength = ofMap(current_distance, 0, max_distance, 0.5, 0);
        float current_amplitude = sin(current_distance * frequency) * amp_strength * amplify_factor;
        mesh_point.z += current_amplitude;

        plane.setVertex(p, mesh_point);
    }
}