Today, however, we can enjoy visually complex games on our mobile devices that are comparable to what can be achieved on a desktop – and as the first mobile graphics processor to deliver true graphics performance, PowerVR technology has been the key from the beginning. The displays on our smartphones are getting bigger and better, so mobile devices offer an even better platform to enjoy graphically appealing games.
What makes a game a competitor of what a user would see on a desktop computer or console? The answer is not just pixels and resolution (although they are important of course). Rather, visual effects that filters apply to what is drawn on the screen, such as blossom, color gradation or vignette.
Depth of field.
Another key technique is to apply the depth of field that anyone familiar with serious photography is familiar with. It is a technique known as bokeh, where you control the focus of the scene by usually blurring the background and bringing the foreground into a sharp relief. It can be used to direct the user’s attention to a particular part of the scene or to improve the mood or emotion in games – a subject so involved that books have been written about it.
Depth of field is indeed a complex thing to achieve in graphics and especially in smartphones, where performance is of course limited by mobile energy budgets. However, it can be implemented and this was impressively demonstrated at the last Game Develop Conference by the depth of field with PowerVR.
This effect is traditionally achieved with a simple blur pass over a standard dynamic range image (SDR image). This can be done quite efficiently, but it doesn’t cut quite aesthetically because the image is relatively smooth and uniform instead of having the sharp highlights you’d want in the ideal case.