1. A method, comprising: performing by a computer: rendering a computer-generated three-dimensional (3D) model as one layer of a multi-layer image, wherein the computer-generated 3D model comprises a description of one or more 3D objects, wherein the description comprises geometry information for one or more surfaces of each 3D object, wherein each layer of the plurality of layers contains information that is different from other layers of the plurality of layers and each layer of the plurality of layers is manipulatable independently of other layers of the plurality of layers, wherein the plurality of layers is combinable to form the multi-layer image, and wherein one or more layers of the multi-layer image comprise multiple image tiles; in response to determining that the 3D model is being manipulated, rendering the 3D model as a single image tile to the one layer of the multi-layer image while at least one other layer of the multi-layer image is rendered as multiple image tiles, wherein said rendering comprises rendering the one layer of the plurality of layers as a single image tile independently of other layers of the plurality of layers; and in response to determining that the 3D model is no longer being manipulated, rendering the 3D model to the one layer of the multi-layer image as a plurality of image tiles, wherein rendering the 3D model as a plurality of image tiles comprises analyzing the full 3D model for each image tile such that said rendering the 3D model as a plurality of image tiles involves more analysis passes of the full 3D model than said rendering the 3D model as a single image tile; wherein a size of each of the plurality of image tiles is equivalent to or smaller than a size of a graphics frame buffer of the computer.