computer graphics Computer graphics deals with generating images with the aid of computers. Today, computer graphics is a core technology in digital photography, film, video games, cell phone and computer displays, and many specialized applications. A great de ...

, the render output unit (ROP) or raster operations pipeline is a hardware component in modern

graphics processing unit A graphics processing unit (GPU) is a specialized electronic circuit designed to manipulate and alter memory to accelerate the creation of images in a frame buffer intended for output to a display device. GPUs are used in embedded systems, mobi ...

s (GPUs) and one of the final steps in the rendering process of modern

graphics cards A graphics card (also called a video card, display card, graphics adapter, VGA card/VGA, video adapter, display adapter, or mistakenly GPU) is an expansion card which generates a feed of output images to a display device, such as a computer moni ...

. The

pixel pipeline In computer graphics, a computer graphics pipeline, rendering pipeline or simply graphics pipeline, is a conceptual model that describes what steps a graphics system needs to perform to Rendering (computer graphics), render a ...

s take

pixel In digital imaging, a pixel (abbreviated px), pel, or picture element is the smallest addressable element in a raster image, or the smallest point in an all points addressable display device. In most digital display devices, pixels are the smal ...

(each pixel is a dimensionless point) and

texel Texel (; Texels dialect: ) is a municipality and an island with a population of 13,643 in North Holland, Netherlands. It is the largest and most populated island of the West Frisian Islands in the Wadden Sea. The island is situated north of De ...

information and process it, via specific

matrix Matrix most commonly refers to: * ''The Matrix'' (franchise), an American media franchise ** ''The Matrix'', a 1999 science-fiction action film ** "The Matrix", a fictional setting, a virtual reality environment, within ''The Matrix'' (franchis ...

and vector operations, into a final pixel or depth value; this process is called

rasterization In computer graphics, rasterisation (British English) or rasterization (American English) is the task of taking an image described in a vector graphics format (shapes) and converting it into a raster image (a series of pixels, dots or lines, whic ...

. Thus, ROPs control

antialiasing Anti-aliasing may refer to any of a number of techniques to combat the problems of aliasing in a sampled signal such as a digital image or digital audio recording. Specific topics in anti-aliasing include: * Anti-aliasing filter, a filter used be ...

, when more than one sample is merged into one pixel. The ROPs perform the transactions between the relevant

buffer Buffer may refer to: Science * Buffer gas, an inert or nonflammable gas * Buffer solution, a solution used to prevent changes in pH * Buffering agent, the weak acid or base in a buffer solution * Lysis buffer, in cell biology * Metal ion buffer * ...

s in the

local memory This glossary of computer hardware terms is a list of definitions of terms and concepts related to computer hardware, i.e. the physical and structural components of computers, architectural issues, and peripheral devices. A ...

– this includes writing or reading values, as well as blending them together. Dedicated antialiasing hardware used to perform hardware-based antialiasing methods like MSAA is contained in ROPs. All data rendered has to travel through the ROP in order to be written to the

framebuffer A framebuffer (frame buffer, or sometimes framestore) is a portion of random-access memory (RAM) containing a bitmap that drives a video display. It is a memory buffer containing data representing all the pixels in a complete video frame. Modern ...

, from there it can be transmitted to the display. Therefore, the ROP is where the GPU's output is assembled into a

bitmap In computing, a bitmap is a mapping from some domain (for example, a range of integers) to bits. It is also called a bit array A bit array (also known as bitmask, bit map, bit set, bit string, or bit vector) is an array data structure that c ...

ped image ready for display. Historically the number of ROPs,

texture mapping unit In computer graphics, a texture mapping unit (TMU) is a component in modern graphics processing units (GPUs). They are able to rotate, resize, and distort a bitmap image to be placed onto an arbitrary plane of a given 3D model as a texture, in a ...

s (TMUs), and

shader In computer graphics, a shader is a computer program that calculates the appropriate levels of light, darkness, and color during the rendering of a 3D scene - a process known as ''shading''. Shaders have evolved to perform a variety of spec ...

processing units/ stream processors have been equal. However, from 2004, several

GPU A graphics processing unit (GPU) is a specialized electronic circuit designed to manipulate and alter memory to accelerate the creation of images in a frame buffer intended for output to a display device. GPUs are used in embedded systems, mobi ...

s have decoupled these areas to allow optimum transistor allocation for application workload and available memory performance. As the trend continues, it is expected that graphics processors will continue to decouple the various parts of their architectures to enhance their adaptability to future graphics applications. This design also allows chip makers to build a modular line-up, where the top-end GPUs are essentially using the same logic as the low-end products. Wednesday, 9 June 2021

References

3D rendering {{Compu-graphics-stub

See also

References