Because MVC doesn't fit in the architecture of a game. The dataflow for a game is entirely different than that of a enterprice application, because it's not as event driven and there is often a (very) tight millisecond budget in which to perform these operations. There are a lot of things that need to happen in 16.6 milliseconds so it's more beneficial to have a 'fixed' and rigid data pipeline that processes the data you need on screen in exactly that time.

Also, the separation is there; most of the time it's just not wired the same way as the MVC pattern. There is a rendering engine (View), user input handling (Controller) and the rest such as gameplay logic, ai, and physics (Model). Think about it; if you're fetching user input, running the ai and rendering the image 60 times per second, then why would you need an Observer between the model and the view to tell you what has changed? Don't interpret this as me saying that you don't need the Observer pattern in games, you do, but in this case you really don't. You're doing all that work, every frame, anyway.

Although TDD is hardly ever used in development studios, we do use Agile practices towards software development and SCRUM seems to be the popular choice at least here in Europe. The reason is simple, the changes come from everywhere. The artists might want more texture budget, larger worlds, more trees while the designers want a richer story (more content on disk), a streaming world and the publishers want you to finish on time, and on budget and so does the marketing department. And apart from that, the "state of the art" keeps changing rapidly.

That doesn't mean that we don't do testing either, most studios have large Q&A departments, run loads of regression tests and do unit tests on a regular basis. However, there's hardly any point doing unit tests upfront because a large part of the bugs are art/graphics related (holes in collision meshes, wrong textures whatever, glitch in the depth of field shader) that unit tests can't cover. And besides working code, the most important factor of any game is that it's fun, and there's no unit testing that.

Also remember that in the console world this is even different still, because you're programming more for the hardware then for anything else. This generally (PS2/PS3) means that the flow of the data is way more important then the flow of the code in nearly every case; due to performance considerations.

Because MVC doesn't fit in the architecture of a game. The dataflow for a game is entirely different than that of a enterprice application, because it's not as event driven and there is often a (very) tight millisecond budget in which to perform these operations. There are a lot of things that need to happen in 16.6 milliseconds so it's more beneficial to have a 'fixed' and rigid data pipeline that processes the data you need on screen in exactly that time.

Also, the separation is there; most of the time it's just not wired the same way as the MVC pattern. There is a rendering engine (View), user input handling (Controller) and the rest such as gameplay logic, ai, and physics (Model). Think about it; if you're fetching user input, running the ai and rendering the image 60 times per second, then why would you need an Observer between the model and the view to tell you what has changed? Don't interpret this as me saying that you don't need the Observer pattern in games, you do, but in this case you really don't. You're doing all that work, every frame, anyway.

Although TDD is hardly ever used in development studios, we do use Agile practices towards software development and SCRUM seems to be the popular choice at least here in Europe. The reason is simple, the changes come from everywhere. The artists might want more texture budget, larger worlds, more trees while the designers want a richer story (more content on disk), a streaming world and the publishers want you to finish on time, and on budget and so does the marketing department. And apart from that, the "state of the art" keeps changing rapidly.

That doesn't mean that we don't do testing either, most studios have large Q&A departments, run loads of regression tests and do unit tests on a regular basis. However, there's hardly any point doing unit tests upfront because a large part of the bugs are art/graphics related (holes in collision meshes, wrong textures whatever, glitch in the depth of field shader) that unit tests can't cover. And besides working code, the most important factor of any game is that it's fun, and there's no unit testing that.

Also remember that in the console world this is even different still, because you're programming more for the hardware then for anything else. This generally (PS2/PS3) means that the flow of the data is way more important then the flow of the code in nearly every case; due to performance considerations. Which nullifies the use of TDD as an architectural tool in most cases. Good OOP code generally has bad dataflow, making it hard to vectorize and parallelize.

Because MVC doesn't fit in the architecture of a game. The dataflow for a game is entirely different than that of a enterprice application, because it's not as event driven and there is often a (very) tight millisecond budget in which to perform these operations. There are a lot of things that need to happen in 16.6 milliseconds so it's more beneficial to have a 'fixed' and rigid data pipeline that processes the data you need on screen in exactly that time.

Also, the separation is there; most of the time it's just not wired the same way as the MVC pattern. There is a rendering engine (View), user input handling (Controller) and the rest such as gameplay logic, ai, and physics (Model). Think about it; if you're fetching user input, running the ai and rendering the image 60 times per second, then why would you need an Observer between the model and the view to tell you what has changed? Don't interpret this as me saying that you don't need the Observer pattern in games, you do, but in this case you really don't. You're doing all that work, every frame, anyway.

Although TDD is hardly ever used in development studios, we do use Agile practices towards software development and SCRUM seems to be the popular choice at least here in Europe. The reason is simple, the changes come from everywhere. The artists might want more texture budget, larger worlds, more trees while the designers want a richer story (more content on disk), a streaming world and the publishers want you to finish on time, and on budget and so does the marketing department. And apart from that, the "state of the art" keeps changing rapidly.

That doesn't mean that we don't do testing either, most studios have large Q&A departments, run loads of regression tests and do unit tests on a regular basis. However, there's hardly any point doing unit tests upfront because a large part of the bugs are art/graphics related (holes in collision meshes, wrong textures whatever, glitch in the depth of field shader) that unit tests can't cover. And besides working code, the most important factor of any game is that it's fun, and there's no unit testing that.

Because MVC doesn't fit in the architecture of a game. The dataflow for a game is entirely different than that of a enterprice application, because it's not as event driven and there is often a (very) tight millisecond budget in which to perform these operations. There are a lot of things that need to happen in 16.6 milliseconds so it's more beneficial to have a 'fixed' and rigid data pipeline that processes the data you need on screen in exactly that time.

Also, the separation is there; most of the time it's just not wired the same way as the MVC pattern. There is a rendering engine (View), user input handling (Controller) and the rest such as gameplay logic, ai, and physics (Model). Think about it; if you're fetching user input, running the ai and rendering the image 60 times per second, then why would you need an Observer between the model and the view to tell you what has changed? Don't interpret this as me saying that you don't need the Observer pattern in games, you do, but in this case you really don't. You're doing all that work, every frame, anyway.

Although TDD is hardly ever used in development studios, we do use Agile practices towards software development and SCRUM seems to be the popular choice at least here in Europe. The reason is simple, the changes come from everywhere. The artists might want more texture budget, larger worlds, more trees while the designers want a richer story (more content on disk), a streaming world and the publishers want you to finish on time, and on budget and so does the marketing department. And apart from that, the "state of the art" keeps changing rapidly.

That doesn't mean that we don't do testing either, most studios have large Q&A departments, run loads of regression tests and do unit tests on a regular basis. However, there's hardly any point doing unit tests upfront because a large part of the bugs are art/graphics related (holes in collision meshes, wrong textures whatever, glitch in the depth of field shader) that unit tests can't cover. And besides working code, the most important factor of any game is that it's fun, and there's no unit testing that.

Also remember that in the console world this is even different still, because you're programming more for the hardware then for anything else. This generally (PS2/PS3) means that the flow of the data is way more important then the flow of the code in nearly every case; due to performance considerations.