Operation (Windows NT)

Blending, using a destination alpha value

The application needs an alpha buffer if it calls the glBlendFunc function with one of the following values:

DST_ALPHA

ONE_MINUS_DST_ALPHA

ONE_MINUS_DST_COLOR

SRC_ALPHA_SATURATE

In conformance with OpenGL, glReadPixels returns 1.0 for all alpha values, and OpenGL uses 1.0 for all destination alpha values when computing blending factors.

Note that all alpha related aspects of the rasterization and per-fragment portions of the OpenGL pipeline (blending, alpha test, alpha related texturing functionality) are supported by PowerStorm 300/350 PCI graphics controllers on the Windows NT Alpha platform.

_________________________ Caution ___________________________

If an application calls wglChoosePixelFormat to request a pixel format with alpha planes, a generic pixel format will be chosen. In this case OpenGL operations will not be hardware accelerated, thus severely degrading performance.

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5.3.3.2.3 Overlay Planes

PowerStorm 300/350 PCI graphics controllers on the Windows NT Alpha platform provide hardware support for 8-bit, double-buffered overlay planes. Note that for performance reasons, not all pixel formats support overlay planes. If you do not require overlay planes, selecting a pixel format without overlay support will ensure maximum performance.

5.3.3.2.4 Stencil Planes

The PowerStorm display driver provides hardware support for a 4-bit stencil buffer. Note that for performance reasons, not all pixel formats support stencil planes. If you do not require stencil planes, selecting a pixel format without stencil planes will ensure maximum performance. The availability of pixel formats with stencil planes can be disabled by using the Display Applet.

5.3.3.2.5 SoftImage Customizations

When using PowerStorm 300/350 PCI graphics controllers on the Windows NT Alpha platform with Microsoft’s SoftImage, you should enable SoftImage Customizations using the Display Applet. This will ensure maximum performance and compatibility with SoftImage.

PowerStorm 300 AGP and 300/350 PCI Graphics Controllers 5–17

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Compaq 300 manual ∙ Blending, using a destination alpha value

300 specifications

The Compaq 300, introduced in the early 1990s, marked a pivotal moment in personal computing, combining cutting-edge technology with user-centric design. This desktop system was targeted at both business professionals and home users, reflecting the growing demand for powerful yet affordable computing solutions.

One of the main features of the Compaq 300 was its robust Intel processor. It originally shipped with various configurations of Intel's 80486 microprocessor, which provided a significant performance boost over its predecessors. The 486 architecture enabled users to run more complex applications, enhancing productivity and making it suitable for tasks ranging from word processing to graphics editing.

In terms of memory, the Compaq 300 supported up to 16MB of RAM, which was substantial for its time, allowing seamless multitasking of programs. The system typically included a 120MB IDE hard drive, which facilitated ample storage for documents and software, a critical aspect for users who needed to manage large volumes of data.

The Compaq 300 featured an integrated graphics card based on the popular VGA standard, enabling clear display quality for applications and gaming. Notably, its 14-inch CRT monitor that accompanied the system offered crisp visuals and an optimal viewing experience for users.

Another characteristic of the Compaq 300 was its expandability. The desktop came equipped with several expansion slots, allowing users to easily add components such as sound cards, network cards, or additional storage drives. This feature provided users with the flexibility to upgrade their systems as technology evolved, ensuring longevity in a rapidly changing landscape.

The Compaq 300 also showcased advanced connectivity options for its time. It included multiple serial and parallel ports, providing versatile connectivity with peripherals like printers, scanners, and modems. This adaptability was crucial, especially as businesses began to integrate more technology into their operations.

Durability and reliability were hallmarks of Compaq's design philosophy, and the Compaq 300 was no exception. Its solid construction and dependable components appealed to users who required a trustworthy system for daily tasks.

Overall, the Compaq 300 epitomized the intersection of performance, expandability, and reliability in desktop computing. Its innovative features and thoughtful design paved the way for future developments in the personal computer industry, making it a noteworthy entry in the history of computing technology.