Shader

In <a href="/facts/Computer_graphics/lapBE8wv">computer graphics</a>, a shader is a <a href="/facts/Computer_program/e38jH9N9">computer program</a> that calculates the appropriate levels of <a href="/facts/Light/jeofpMn4">light</a>, <a href="/facts/Darkness/T8v58NK3">darkness</a>, and <a href="/facts/Color/XDvW7ESP">color</a> during the <a href="/facts/Rendering_(computer_graphics)/YYxfnmAq">rendering</a> of a <a href="/facts/3D_scene/GfIomenN">3D scene</a>—a process known as <a href="/facts/Shading/ewcDEfda">shading</a>. Shaders have evolved to perform a variety of specialized functions in computer graphics <a href="/facts/Special_effects/LHutf1pg">special effects</a> and <a href="/facts/Video_post-processing/cDPyuE2W">video post-processing</a>, as well as <a href="/facts/General-purpose_computing_on_graphics_processing_units/roBwsPY2">general-purpose computing on graphics processing units</a>.
Traditional shaders calculate <a href="/facts/Rendering_(computer_graphics)/YYxfnmAq">rendering</a> effects on graphics hardware with a high degree of flexibility. Most shaders are coded for (and run on) a <a href="/facts/Graphics_processing_unit/PTK1RQVp">graphics processing unit</a> (GPU), though this is not a strict requirement. Shading languages are used to program the GPU's <a href="/facts/Rendering_pipeline/XnF55m31">rendering pipeline</a>, which has mostly superseded the <a href="/facts/Fixed-function_pipeline/GfIomenN">fixed-function pipeline</a> of the past that only allowed for common <a href="/facts/Vertex_shader/qfhkKFwA">geometry transforming</a> and <a href="/facts/Pixel_shader/qfhkKFwA">pixel-shading</a> functions; with shaders, customized effects can be used. The <a href="/facts/3d_coordinates/lkTqvMmB">position</a> and <a href="/facts/Color/XDvW7ESP">color</a> (<a href="/facts/Hue/9qufc1ap">hue</a>, <a href="/facts/Colorfulness/WaePy7Ga">saturation</a>, <a href="/facts/Brightness/e93R5I4b">brightness</a>, and <a href="/facts/Contrast_(vision)/zD9F91Je">contrast</a>) of all <a href="/facts/Pixel/UzwBvXBV">pixels</a>, <a href="/facts/Vertex_(computer_graphics)/lj0ltT3g">vertices</a>, and/or <a href="/facts/Texture_(computer_graphics)/9gDTsuXN">textures</a> used to construct a final rendered image can be altered using <a href="/facts/Algorithm/fnl5NmRt">algorithms</a> defined in a shader, and can be modified by external <a href="/facts/Variable_(computer_science)/VoCKtwml">variables</a> or textures introduced by the computer program calling the shader.
Shaders are used widely in <a href="/facts/Filmmaking/GL8DJm3W">cinema</a> <a href="/facts/Post_processing_(images)/cDPyuE2W">post-processing</a>, <a href="/facts/Computer-generated_imagery/ThJ2gh1X">computer-generated imagery</a>, and <a href="/facts/Video_games/vmTdNASJ">video games</a> to produce a range of effects. Beyond simple lighting models, more complex uses of shaders include: altering the <a href="/facts/Hue/9qufc1ap">hue</a>, <a href="/facts/Colorfulness/WaePy7Ga">saturation</a>, <a href="/facts/Brightness/e93R5I4b">brightness</a> (<a href="/facts/HSL_and_HSV/opaXI7FM">HSL/HSV</a>) or <a href="/facts/Contrast_(vision)/zD9F91Je">contrast</a> of an image; producing <a href="/facts/Defocus_aberration/AuE5r5Wv">blur</a>, <a href="/facts/Light_bloom/haIQqEwK">light bloom</a>, <a href="/facts/Volumetric_lighting/L8crqTqH">volumetric lighting</a>, <a href="/facts/Normal_mapping/7YmzxkPp">normal mapping</a> (for depth effects), <a href="/facts/Bokeh/BahN1Q2R">bokeh</a>, <a href="/facts/Cel_shading/0n5Mw9NA">cel shading</a>, <a href="/facts/Posterization/SEdYoKRj">posterization</a>, <a href="/facts/Bump_mapping/c97rLmK6">bump mapping</a>, <a href="/facts/Distortion_(optics)/NLm05Rls">distortion</a>, <a href="/facts/Chroma_key/PJ2XcxFR">chroma keying</a> (for so-called "bluescreen/<a href="/facts/Greenscreen/PJ2XcxFR">greenscreen</a>" effects), <a href="/facts/Edge_detection/9VplpIcS">edge</a> and <a href="/facts/Motion_detection/SXwDdwrx">motion detection</a>, as well as <a href="/facts/Psychedelia/aPaJ3R3C">psychedelic</a> effects such as those seen in the <a href="/facts/Demoscene/yKunscS7">demoscene</a>.

Shader open-in-new

Shader