Why Three Views are Necessary
We live in a three-dimensional (physicists may say four, fantasists say more) world. To visually represent that, one needs to meld length, width, and depth. Absent any one and the result is a bizarre view of the world.
buy priligy online in india Hence, we can start with something as seemingly complex as this flat, 2-dimensional—up and down, left and right—drawing . . .
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And get something that looks a bit more real-worldly with not only left-right, up-down, but also front-back.
What if one dimension is missing?
Archaeologists, historians, and other scholars have for years been wondering what the Confederate submersible H. L. Hunley really looked like. The historic vessel was discovered a number of years ago, has been raised, and is currently under minute excavation and discovery in Charleston, South Carolina. Many questions have been answered, especially what she looked like. (https://hunley.org/) Here is a link to the most recent detailed (extremely!) analysis of the vessel by the Underwater Archaeology Branch of the Naval History and Heritage Command. (https://www.history.navy.mil/research/underwater-archaeology/sites-and-projects/ship-wrecksites/hl-hunley/recovery-report.html)
But before this, to envision the boat, historians had to rely on a written record, no known photographs exist. There were a few sketches and one watercolor wash painting by R. G. Skerrett, which gave a fair idea of her form, but they—as is all art—were reliant on the artist’s eye and especially, hand. What is real? (Naval History and Heritage Command)
One of the early references was this two-view tracing of a predecessor boat, the “Rebel Submarine Ram” Pioneer. It was from a contemporary 1864 Civil War report from U.S. Navy Fleet Engineer William H. Shock to the Assistant Secretary of the Navy. (National Archives and Records Administration)
The upper drawing shows a side view of the ram, with some interior details. The bottom drawing shows a top view looking down of the vessel.
There is nothing, however, to show us the third dimension, a front view. The illustrations below will demonstrate the impact of that missing third dimension.
All the views you will see were made with this set of lines that I pulled from the original drawing. The only thing that is different between the pairs of renders is that in one, I let the original drawings determine the final shapes, and in the other one I assumed the third dimension to be curved.
These are the top views of the two versions, the lower has many more lines because those are necessary to draw the curves in the 3D rendering of these lines. Note however that the external lines of each part are identical. This reflects the lines’ origins from the lines pulled from the original.
This shows the resultant 3D render.
Similarly, here are the side views, again with the lower drawing and render showing the addition of curved lines.
And this drawing shows the resultant third dimension, the front views, based on the base (left) and curved lines.
Here are the resultant images in full 3D.
Note that, both 3D renderings match the original 2D drawing. Which is correct?
While that is certainly obvious, this is just an illustration of issues that can occur in the absence of information.
This rendering further illustrates the need for three views. Notice the two highlighted areas.
Many times with all three views provided, even that information is not enough. Sometimes it is a confusion on the part of the original craftsman with regard to how a particular line should be depicted in each of the three views. More often, however, lines are hidden. These require either additional drawings, or better yet, a perspective drawing of their intersections. No examples come immediately to mind, but I am certain at least one will crop up on an upcoming drawing. I will address that when it happens.
This final rendering shows the curved 3D version over the original lines. The other version would similarly line up.
