Silicon Graphics released to the public in 1992 its Open Graphics Library or OpenGL graphics compute application programming interface or API as a replacement to its previous IRIS GL graphics API. Several graphics APIs also emerged during the 1990s. These include DirectX or Direct3D from Microsoft. OpenGL managed to remain afloat and became one of the standards in the industry. The control over this graphics API standard was transferred to the Khronos Group in 2006 and the newer Vulkan graphics API standard was introduced in 2016. OpenGL is now considered an old technology but it remains popular among developers.
Pros of OpenGL: Advantages and Notable Features
OpenGL is a cross-language and cross-platform graphics API used for rendering 2D and 3D vector graphics. This means that it acts as an intermediary between a program or application and a discrete or integrated graphics processor of a computer that allows a more efficient and hardware-accelerate rendering of graphics. OpenGL became popular because of its first-to-market advantage and its platform-independence nature. These encouraged early adoption among software developers and hardware designers or manufacturers. Below are the specific advantages of OpenGL:
1. Platform Independence and Vendor Neutrality
A key advantage of OpenGL is that it is platform-independent or has an extensive cross-platform support. It can be implemented on mainstream operating systems like Windows, macOS, Linux, iOS or iPadOS, and Android. This makes it a more efficient graphics API because developers can use a single code base to develop graphics-demanding software programs or apps, such as video games and simulations, that are intended to run on different devices.
Furthermore, similar to the aforementioned, this graphics API is an open standard. It is not tied to a particular hardware manufacturer and has been supported by a range of graphics processor manufacturers like AMD, Nvidia, and Intel. This further makes it an efficient graphics API and ensures that programs or apps built using this API can run on different brands of graphics processing units without requiring specific hardware optimizations.
2. Demonstrated Performance and Flexible Features
OpenGL directly interfaces with a graphics processing unit to enable hardware-accelerated and efficient graphics rendering. It specifically provides a particular program or app with direct access to the graphics hardware and enables developers to achieve high-quality graphics without compromising speed and visual quality. This is essential in graphics-demanding applications like video games, scientific simulation, and three-dimensional modeling.
This graphics API also features some aspects of low-level and high-level interfacing. The specific low-level aspect gives developers a more granular level of control and the high-level aspect includes a set of abstract functions and concepts that bar them from intricate hardware-specific operations. This middle ground enables substantial control over a range of rendering techniques like vertex manipulation, texture mapping, and lighting effects.
3. Resource Availability and Foundational Nature
There are also other reasons to use or learn OpenGL despite its age. For starters, in terms of resources, it is one of the few graphics APIs that has tons of free learning materials accessible from the official website of Khronos Group, various online forums, and video-sharing platforms. Even generative AI chatbots such as Bing Copilot, ChatGPT, and Google Gemini have been trained in these materials. It also has a large and active community of developers.
Another advantage of OpenGL is that is suitable for beginners. It is a good starting point for individuals who want to learn graphics programming because it can provide foundational knowledge or concepts and it is easier to understand and implement compared to other graphics APIs like Direct3D, Vulkan, and Metal. The skillsets learned from this graphic API can be applied to other newer or more complicated graphics API counterparts or options.
Cons of OpenGL: Disadvantages and Key Limitations
It is important to underscore the fact that OpenGL is old. This can be a drawback for some. Other graphics APIs have emerged. Vulkan is positioned as its successor and Metal is a more specific and optimized alternative. Direct3D is also one of the most popular options out there that has earned a considerable level of support due to the popularity of Windows in personal computing and PC gaming. The performance also varies due to different implementations and the impact of factors such as hardware configurations. Below are the specific disadvantages of OpenGL:
1. Performance Variability and Standards Issues
This graphics API is known for improving tasks that involve 2D or 3D graphics rendering across different supported platforms. However, when it comes to real-world applications, the performance is not guaranteed due to factors such as hardware configuration, driver optimizations, and the nuances of a particular operating system. Developers are still required to test developed programs or apps to ensure that they are optimized to run on different platforms.
It is also important to note that its low-level aspect can sometimes result in performance overhead due to bottlenecks. Optimization is still essential in the development process. Furthermore, because extensions are been rolled out to support new hardware functionalities and technologies, compatibility issues are possible. These extensions are often vendor-specific and may not be available on all operating systems and hardware or specific graphics processors.
2. Development Challenges and Other Considerations
Remember that OpenGL has several low-level aspects and also has limited high-level features, unlike some higher-level graphics APIs. Having more control over the inner workings of a graphic processor increases the potential of a particular program or app for errors and bugs. Preventing or resolving these issues requires developers to have a deeper understanding of the graphic systems and the entire framework of this application programming interface.
It is also possible for developers to implement additional functionalities on top of this graphics API because of the absence of some features found in high-level alternatives like Direct3D. A prime example is its limited user interface support. This graphics API is focused primarily on graphics rendering and has limited built-in features for developing front-end or graphical user interfaces. This limitation requires developers to use additional libraries or frameworks.
3. Competitive Alternative and Deprecation Potential
Direct3D is considered the best alternative to OpenGL on the Windows platform. This graphics API has several unmatched advantages which include more performance potential on computers running on Windows and a strong ecosystem. Metal is also the sole option available on Apple platforms such as macOS and iOS or iPadOS. It is specifically optimized for Apple hardware and is an integral part of its product strategy and semiconductor strategy.
Take note that Apple dropped support on all of its newer platforms. Programs or apps for macOS or iOS can still be developed using OpenGL but will require porting or a translation layer. The Khronos Group has also stopped rolling out new updates that would support modern graphics technologies like ray tracing and upscaling using deep learning. Vulkan has been positioned as its successor. The potential to become obsolete is a key disadvantage of OpenGL.
Takeaways: Advantages and Disadvantages of OpenGL
It is important to underscore the fact that OpenGL remains a popular choice for graphics programming because of its cross-platform support, availability of resources and community support, and its foundational programming environment. However, despite its advantages, its disadvantages become more pronounced when taking into consideration the availability of competitive alternatives. Direct3D remains popular in developing PC games while Metal has become a standard API for Apple platforms. Vulkan is emerging as a suitable successor because it is an OpenGL derivative that addresses its limitations and supports newer graphics technologies.
