Abstract: In the present invention, a combination of asynchronous rendering and synchronous rendering is utilized to render an electronic document on the screen of a computing device. Particularly, a document-rendering application may be configured to draw asynchronously a high-detail version of the document to a rendering cache. This high-detail version is used to paint the document to the screen in a synchronous screen refresh operation. If, during the screen refresh operation, there are parts of the viewport that the asynchronous process has not finished rendering, these missing parts are filled in with a low-detailed version of the document that is painted fast enough to maintain the high screen refresh rate. For example, the low-detailed version of the document may show the basic structure of the document including the background color, layout boxes, and lines. However, other elements of the document may be replaced or excluded entirely from the less-detailed version.

Abstract: In the present invention, a combination of asynchronous rendering and synchronous rendering is utilized to render an electronic document on the screen of a computing device. Particularly, a document-rendering application may be configured to draw asynchronously a high-detail version of the document to a rendering cache. This high-detail version is used to paint the document to the screen in a synchronous screen refresh operation. If, during the screen refresh operation, there are parts of the viewport that the asynchronous process has not finished rendering, these missing parts are filled in with a low-detailed version of the document that is painted fast enough to maintain the high screen refresh rate. For example, the low-detailed version of the document may show the basic structure of the document including the background color, layout boxes, and lines. However, other elements of the document may be replaced or excluded entirely from the less-detailed version.