Viscosity is the resistance to flow (opposite of fluidity). Viscosity depends on primarily on the composition of the magma, and temperature. Higher SiO2 (silica) content magmas have higher viscosity than lower SiO2 content magmas (viscosity increases with increasing SiO2 concentration in the magma). Lower temperature magmas have higher viscosity than higher temperature magmas (viscosity decreases with increasing temperature of the magma).
Google does not specifically recommend either DirectX or OpenGL for Google Earth. You can configure Google Earth to operate in either DirectX or OpenGL rendering modes.If your system crashes or performs poorly in one mode, Google recommends you switch to the other mode.penGL Overview. OpenGL is a platform-neutral, open API for rendering graphic images. Although the API is different, OpenGL provides Google Earth with the same graphics performance enhancements as DirectX. OpenGL was originally developed by Silicon Graphics Incorporated.
The product, re-released as Google Earth in 2005, is available for use on personal computers running Windows 2000 and above, Mac OS X 10.3.9 and above, Linux kernel: 2.6 or later (released on June 12, 2006), and FreeBSD. Google Earth is also available as a browser plugin which was released on May 28, 2008.