For each shot we have made there are many stages that have to be done in order to get the best results. The first stage is to make the movie clip in to an image sequence, this has to be done because Maya will only read Tiff image sequences and if we need to motion track the scene Match Mover will only read image sequences. This was quite awkward at first as we had never use images sequences before. To create the image sequences we used a piece of software called MPEG Streamclip, this allowed us to select the length of clip we wanted and then export in any format we wanted.
The next step in the proces is to import the image sequence and robot in to Maya and then move the camera so that the base grid lines up with the floor of the image sequence. This has to be done so when the robot is placed in the scene it looks as if he is standing on the floor of the clip. Once this is done we had to create polygon planes that fit with the the floor and with any other part of the scene that the robot will be interacting with or that a shadow might be cast on. For example the floor, top of step and side wall.
This will now make the animation a lot easier to get right because there are floor planes to line up the robot with. So naturally the next step in the proces is to animate the robot. Before we had even started any animation in the scenes we decided that it would be best to animate an walk cycle and run cycle so we can just import it when needed instead of animating it for every shot. This saved a lot of time in the animation proces.
Once all the animation is done we have to put lights in to the scene and adjust the settings so that the shadows look realistic. In order to have the shadows cast on the ground of the scene we have to apply a texture to the polygon planes called Use Background. This texture allows the polygon to act the same as any other but it becomes transparent when rendered allowing the shadows to fall on the plane but also allowing the background to show through.
Next is to add texture to the robot and smooth the robot. We found that it is best for us to smooth the robot twice so that all the edges are rounded and look correct. Smoothing the robot changes how the light reacts on the robot and can change the shadows in some cases so we had to go back and check the shadows to see if they still look as we originally wanted them.
Because we have a lot of texture on the robots casing, for example the sceme down the side of him and the springs in the middle of him. When just rendering a simple high quality colour render the inner shadows on the robot didn’t show up as well as we were hoping. In order to get these shadows we found out that we had to add a separate texture to the whole robot called Ambient Occlusion. This calculates the internal shadows and creates a mask of the robot including these shadows. We combine both renders later on in the proces. When rendering the Ambient Occlusion there needs to be no other objects in the scene, such as lights and polygon planes, but we keep the camera and the animation.
Next is rendering and waiting…….
Once Both clips have finished rendering we have to import them both into after affects as well as the movie clip image sequence. Layering them all with the the Movie clip on the botom, then the colour render and then the Ambient Occlusion.
In dooing this the colour version of the render becomes fully masked out by the Ambient which is white and grey. We still want to keep this layer because it is the the internal shadows so we have to and a blend to the ambient occlusion called Multiply which blends it and the colour version together giving the final product realistic internal shadows as well as the original colour and floor shadows. The brightness and contrast can be adjusted on each clip if needed.