CS 475/675 Assignment 4 (Droids - Animation)

The state of the robots, lights and camera can be recorded by pressing `F'. The state is appended to `keyframes.yaml' file. yaml format was used mainly because of the readability of the created file, rather than to avoid parsing text.

`P' is binded to the interpolation and playback function. It reads all the key frames from `keyframes.yaml' interpolates between them and plays them back. For simplicity we have used a constant number of frames between key frames.

Instead of `P', if `R' is used the intermediate frames are copied from the framebuffer and stored to a file.

While playing back using `P', glfw timers in particular glfwGetTime is used to pace the frames at the required rate. The core timing code from main.cpp is:

frame_start = glfwGetTime();

renderGL();
env.draw();
glfwPollEvents();

draw_time = glfwGetTime() - frame_start;

sleep_time_ms = int(1000.0*(frame_time - draw_time));
if( sleep_time_ms > 0.0 )
{
  std::this_thread::sleep_for(std::chrono::milliseconds(sleep_time_ms));
}

glfwSwapBuffers(window);

In short the main thread is made to sleep for any time remaining after rendering a frame and polling for events.

In process as the due date for this part is Nov 27th.

Functionality to move the camera along a Bezier curve has been implemented. To author a Bezier curve a 3D-cursor in the shape of a camera can be turned on by using the key `*'. This cursor can be moved to any position and orientation using the keybindings for moving an object (`TAB' is used to switch 'active object' status from one object to the next). At any point, the cursor's pose can be recorded using `+' and the last pose can be deleted using `-'. These recorded poses are uses as the coordinates of the control polygon, and corresponding Bezier curve is updated each time `+' or `-' is used.

Points on the curve can be sampled and used to animate the camera position on it.