What is Digital 3D Space?
An important idea behind perspective is that every shape and object depicted on the projection plane sends a "ray" to the viewpoint, or our eye.
Computer 3D applications rely heavily on this concept through a process called ray tracing.
Imagine that all objects in a scene emit these theoretical "rays.
" On their way to the viewpoint, they will pass through the projection plane that, in the case of computers, is the screen.
In theory, the screen records what shade, hue, and intensity the pixels on your monitor will appear.
Ray tracing works backwards by working down these "rays" to the objects, while considering if the visible light is from a source or is reflected.
There are many different ways besides ray tracing that computers actually use to figure out what should be displayed on your screen, but it is a good way to picture how the computer is "painting" or "projecting" the 3D objects present in its digital space.
Digital Space Through Project Windows And Virtual Cameras The forms of perspective we most readily accept are the linear forms that most closely resemble the world around us.
Because of this, most of the figures we see in 3D art have been displayed in perspective projection.
However, although perspective is best for finally understanding a composition, it isn't always the best way to view digital space when creating that composition.
Depending on the application you are using, you can look at the same digital space and the objects contained in that space from a variety of different viewpoints.
Now, while you can look at the digital space in perspective from all of these points, perspective provides some obstacles between you and the 3D application.
When the computer projects the space in perspective, it is showing you all three dimensions on your two-dimensional screen.
The problem is, your mouse can only move in two dimensions across the projection plane of your screen.
So, when your mouse clicks on an object, it becomes very difficult for the application to decide if you are just moving an object horizontally (x) and vertically (y), or if you are attempting to move it in depth (z) as well.
To rectify this, 3D applications use something called an orthographic view or projection.
Orthographic projections are views in which the parallel lines in the model do not converge on a vanishing point like they do in perspective; instead, they remain parallel, or at right angles with the projection plane (Ortho means "at right angles to").
This is very unlike the world as we observe it.
Computer 3D applications rely heavily on this concept through a process called ray tracing.
Imagine that all objects in a scene emit these theoretical "rays.
" On their way to the viewpoint, they will pass through the projection plane that, in the case of computers, is the screen.
In theory, the screen records what shade, hue, and intensity the pixels on your monitor will appear.
Ray tracing works backwards by working down these "rays" to the objects, while considering if the visible light is from a source or is reflected.
There are many different ways besides ray tracing that computers actually use to figure out what should be displayed on your screen, but it is a good way to picture how the computer is "painting" or "projecting" the 3D objects present in its digital space.
Digital Space Through Project Windows And Virtual Cameras The forms of perspective we most readily accept are the linear forms that most closely resemble the world around us.
Because of this, most of the figures we see in 3D art have been displayed in perspective projection.
However, although perspective is best for finally understanding a composition, it isn't always the best way to view digital space when creating that composition.
Depending on the application you are using, you can look at the same digital space and the objects contained in that space from a variety of different viewpoints.
Now, while you can look at the digital space in perspective from all of these points, perspective provides some obstacles between you and the 3D application.
When the computer projects the space in perspective, it is showing you all three dimensions on your two-dimensional screen.
The problem is, your mouse can only move in two dimensions across the projection plane of your screen.
So, when your mouse clicks on an object, it becomes very difficult for the application to decide if you are just moving an object horizontally (x) and vertically (y), or if you are attempting to move it in depth (z) as well.
To rectify this, 3D applications use something called an orthographic view or projection.
Orthographic projections are views in which the parallel lines in the model do not converge on a vanishing point like they do in perspective; instead, they remain parallel, or at right angles with the projection plane (Ortho means "at right angles to").
This is very unlike the world as we observe it.
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