Graphics stack: Difference between revisions

Then next level is the renderer, which is where individual images or sections of images get created. This is where you really see 3-D becoming a separate thing, as most systems prior to, say, 2007 would have used a strictly 2-D rendering for everything that didn't specifically require 3-D rendering, due to the need for hardware acceleration for practical real-time 3-D rendering at the time. As BrendanThere has pointedbeen out before, right now thea Cycle of Reincarnation for graphics rendering has been swinginggoing towardsbetween CPU-driven rendering sincededicated theGPU 2012rendering orand soback, thoughwith dedicatedcurrent renderingsystems hardwareoften isusing stillboth dominant atfor thedifferent momentpurposes. Note, however, that the graphics rendering Wheel of Incarnation has been rolling since the very first days of computer graphics in the early 1960s, so it is a good guess that this won't be the last word on the subject.

AnywayFor example, the Mesa properlibrary used in many Linux systems started out in the 1990s as a software 3-D renderer, but currently is used to sort of abstract the rendering inprocess, aallowing wayit thatto theuse softwarehardware renderingacceleration iswhile moreproviding ofsoftware rendering a fallback mode.

This is where you need to decide how you are going to handle the differences between rendering 2-D images such as basic windows and widgets, and the more impressive but also more processing-intensive 3-D rendering. While the fact that you can treat 2-D as a special case of 3-D, means it is tempting to use 3-D for everything, but that approach has some significant down sides, especially on older hardware;. youYou may need to consider where you can use less general 2-D rendering to avoid a lot of hardware crunching where possible.

You also need to look at how you separate different renderable elements such as glyphs (letters, digits, text symbols, etc.), widgets (window borders, menus, icons, the mouse pointer), 2-D images such as drawings and pictures, 3-D manipulatablemanipulable objects, etc. This relates, and raises the issue in, the next layer of the stack, the compositor. However, before that I need to mention another part of this layer, the widget toolkit.