Nothing you're saying suggests you understand what OpenGL actually is, how it works or how it's implemented, or even know what an API is. I'm not sure why you keep posting stuff as fact that is completely wrong.
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Why Open GL and Not DirectX should be the API of Choice for AAA Games
- Thread starter Gregster
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Nothing you're saying suggests you understand what OpenGL actually is, how it works or how it's implemented, or even know what an API is. I'm not sure why you keep posting stuff as fact that is completely wrong.
So you keep saying, educate me. point out where i'm going wrong and detail what's right.
OpenGL is nothing more than basically a language for 3d rendering. It isn't linked to any operating system or any hardware. The graphics drivers implement it on any given system.
Valve ported games from DirectX to OpenGL. They can only use OpenGL as it exists and is supported via the drivers, they have no control over it and can't change it. The graphics drivers dictate what level of support there is - not Valve, Microsoft or anybody else, so if a game uses OpenGL in SteamOS it can use OpenGL in Windows.
An API is middle-ware.
Your Operating system connects you to your peripherals, including your screen and what you see on it, the drivers connect the operating system to your GPU, which generates what you see on that screen.
Direct X or OpenGL connects the Game or software to your GPU giving it instruction of how to render it.
Direct X does this in a very inefficient and clumsy way, causing bottlenecks, its a higher level API, it does not go directly to the GPU, instead it goes the scenic route
OpenGL is much more efficient, thats why the performance is much better.
Mantle is the same thing, and it does go directly to the GPU removing the bottlenecks and improving performance.
Mantle also does this in the same way the PS4 and xBox One API's get to their Hardware, which is not the same way Direct X gets to the Hardware, Mantle bypasses Direct X on the Desktop.
Because both Consoles use the same Hardware they access it in the same way, Mantle copies that on the Desktop, so the middle-ware on all 3 platforms are the same, but by name, and used by every Game developer making games for the PS4, xBox one and PC.
Anyway... i'm off for some dinner.
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Slightly off topic, but still about API's.
I was reading one of the AMD graphics card reviews the other day and it heavily suggested that Mantle was more or less a direct rip of the API developed for the Xbox one, which of course could have been written by Microsoft them selves.
I was reading one of the AMD graphics card reviews the other day and it heavily suggested that Mantle was more or less a direct rip of the API developed for the Xbox one, which of course could have been written by Microsoft them selves.
Shows how much you know about Open GL.
When Vista was in development MS made a big deal about how Open GL wouldn't be properly supported under Vista, couldn't be properly supported and would run via a "lite" functionality wrapper for backwards compatibility.
At the time development on Open GL had also slipped behind DX and so all but the most hardcore developers moved away from it even though MS relatively quickly changed their tune on Open GL support in Vista, the damage was done.
Moving on its a bit of a fallacy to say Open GL = faster than Direct3D, they both have areas they are more efficent at but at a simplified level neither is overall faster - what Open GL does allow, which is much more restricted on D3D, is a clued up developer to more finely tune their feature implementation to get better performance but this comes at a cost that the API typically requires a higher level of experience and skill to work with - another part of the reason DX has been relatively widely adopted is that it is far more accessible for an inexperienced programmer.
To give some kind of idea of the difference in working with DX and Open GL say you were wanting to load an image from a file on disc and use it as a texture on an object in your game - with DX you can simply call the function D3DXCreateTextureFromFile specifying what rendering device and filename to use and it will go away and load all the data itself and sets a pointer to where that data is now loaded into memory for use. With Open GL you'd have to write a function to load the image file (or use an off the shelf image library), create a buffer, parse the image data into the buffer depending on the file format you were using, create a texture buffer on the open gl device, mess around with image dimensions and filtering options, etc. copy all the data over before you can even do anything else - there are pre-existing libraries to implement some of this or even do it in one go for you but that then adds an extra layer of code to your project and ostensibly brings you back to DX levels of (in)efficiency if your doing something that could be hand optimised for better performance.
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Anandtech speculated that Mantle was the underlying API on the consoles, but it is nothing but speculation. That doesn't mean developers would be able to use Mantle on the consoles, just that it would be used behind the scenes. Even if it is true, and they can use Mantle, it doesn't mean that they necessarily will. A game using OpenGL on PS4 could just as easily be ported to Windows or Linux/SteamOS, and wouldn't be limited to AMD hardware.
AMD Roy and AMD PR Thracks aka AMD RADEON TWITTER, both linked to that article as well saying it was a good read. In other words, its most likely spot on. Anandtech and AMD have a good relationship but it stops short of the sort of relationship you see with Pcper/Nvidia.
that is the case does this mean that Microsoft wrote it, or did they farm it out to a third party.
Soldato
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I went through HL in OGL on the voodoo 3. It also supported Glide IIRC. OpenGL needs to make a comeback.
Yeeeaaah... worryingly I wouldn't take either of their word as fact despite them working for the companies involved when it comes to the technical data... they've been wrong, very wrong more than once before even if you don't want to hear or believe that.
EDIT: Thats not to say they are always wrong or wrong on this just that I'd be wary of using them too much alone as hard confirmation of something.
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Soldato
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It's not a stretch to say its at least very similar. Considering it's coming into play along side the new consoles for one before you even begin to look under the hood. It doesn't really matter, does it?
There's a lot said about Mantle with very little information to go on. We only really know that it's an API, it offers some lower level functionality than OpenGL or DirectX, and it is supported by AMD on GCN.
If AMD's written a low level hardware API for GCN specifically, that's great for the consoles, but not much good for PCs, as it'd only be usable while AMD sticks with that architecture. It'd mean messy wrapper layers later on, which would destroy any performance benefits on future hardware.
If it's a more generic low level API, there'd be no reason that nvidia couldn't implement it too (providing it's not a closed API), and it'd be competing with OpenGL as a cross platform API.
If AMD's written a low level hardware API for GCN specifically, that's great for the consoles, but not much good for PCs, as it'd only be usable while AMD sticks with that architecture. It'd mean messy wrapper layers later on, which would destroy any performance benefits on future hardware.
If it's a more generic low level API, there'd be no reason that nvidia couldn't implement it too (providing it's not a closed API), and it'd be competing with OpenGL as a cross platform API.
Soldato
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How do 'we' know this?
Before Nvidia/Pcper launched the FCAT frame pacing PR assault on AMD, AMD went to anandtech to give their take on things regarding the whole frame pacing issue. Obviously AMD were tipped off on what was coming. They mapped out the problems and said we acknowledge there is an issue and we will address it. They also admitted they'd never tested for it previously. This was a day or two before the whole thing started.
AMD could have chosen any other tech site. Anand were the only ones running the article with exclusive quotes from AMD. Although anand are fair to both sides, they're definitely not anti amd at all, unlike some other sites.
Who launched the 'AMD has issues' 4k pr campaign just ahead of the 290X Hawaii launch? Spearheaded by Nvidia/Pcper again. Ryan Shrout from pcper on record as saying his source in the AMD driver team said no fix was coming for 4k issues/frame pacing for the foreseeable future, if at all. That was the reason for him posting the 4k issues article. No fix coming anytime soon. 1 week later 290X arrives with hardware frame pacing as part of the gpu and 4k issues solved as i posted about here.
I've debated this a billion times here and elsewhere so ill leave it there for now as im getting way off track of the topic at hand. If anyone wants a further response from me regarding this drop me a trust.
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