Constructive drawings

[Xeon_OND]

At work, I've nothing to do in the morning and I'm sick of drawing the stationery (pencils, erasers, staplers) on my desk, and I think it's good to draw from imagination as well (I work purely from life currently).

So, I guess I need to learn how to draw the 4 geometric shapes from any perspective, but where do I start?

Do I just imagine cubes, cylinders, cones and spheres in my mind tilted at a certain angle, and then try to get that down on paper?

I'm not even sure where to begin! LOL :D

See ye,
Xeon

[Mr_S_14]

Try drawing them in perspective, first draw a basic square on a floor in perspective, and then draw lines from each corner to the opposite corner, and then lines through the middle of the squares [X] that go like this [+] these points are where the ellipse of the circle meets the square, variations of this will help you rock cylinders.
I also had an excercise where I had to draw the Negative space of mostly Cylindrical objects (I used hella Wine glasses, a couple wine botttles, and a few candles, but anything will work. anyways, Draw the Negative space, focusing on proportions and the lines around the Objects, and then from there, try to perfect the ellipses of the cylinders, drawing not just the part you can see, but the back part as wel(tip some cylinders on their sides and at angles.
Oh, My Friend really loves doing Blind Contour/line drawings. Don't just draw the objects, but reflections as well, withouth looking at the paper. just the thing... sometimes you might get some cool stuff. most the time it's just gibberish, but it's a good exercise.

Have fun.
G'Night,
Mr_S_14

[Mr_S_14]

Search cyllinders in perspective, some stuff is just bs, but you might find some good informations as well, I learned ellipses/cylinders by tracing a CD , Drawing a square around it, and then plotting the points it meets the [X] and [+] and just brought the points up as lines to Eye level and created it in perspective from there. What I just said only makes sense if you've seen or done it... anyways, learn the "basic rules" of art so you can break them, push them ,and manipulate them. The great thing about rules is... They don't have to make sense as long as they're consistent, they work. lol

[dose]

Start with a box. Get that in correct perspective. Then learn how to fit the solids inside. It can help to construct the solids using cross-sections.

[Zazerzs]

"Do I just imagine cubes, cylinders, cones and spheres in my mind tilted at a certain angle, and then try to get that down on paper?"

Pretty much. I'm doing these sort of warm ups in the morning. Just starting off with cubes or rectangles in projection, then moving on to spheres and cylinders.

Projection is slightly different than in perspective but its close, all one would need to do would be to converge the lines a little and it would be in perspective. (or close to it) good enough for quick sketching.

One thing that you will need to get down is how to construct a circle on a plane, if you don't know the formula I'll post the steps.

There is also an exercise where you draw a curvy line then attach the cubes to it. I'll do some of those today for examples.

ok here are the examples:Bic pen on newsprint: any ID guys will rip em apart but as for examples they should work.

[Xeon_OND]

Thanks Dose and S-14!

"Do I just imagine cubes, cylinders, cones and spheres in my mind tilted at a certain angle, and then try to get that down on paper?"

Pretty much. I'm doing these sort of warm ups in the morning. Just starting off with cubes or rectangles in projection, then moving on to spheres and cylinders.

Projection is slightly different than in perspective but its close, all one would need to do would be to converge the lines a little and it would be in perspective. (or close to it) good enough for quick sketching.

One thing that you will need to get down is how to construct a circle on a plane, if you don't know the formula I'll post the steps.

There is also an exercise where you draw a curvy line then attach the cubes to it. I'll do some of those today for examples.

ok here are the examples:Bic pen on newsprint: any ID guys will rip em apart but as for examples they should work.
Thanks for the illustration! Come to think of it, this is actually very challenging.

Regarding the cubes on the curves, I assume that you're relying on "feel" and estimation to decide how much of each side to show?

For constructing a circle on a plane, maybe you could post the stuff here. I'm not sure if you're talking about drawing an ellipse. :)

I'm gonna try this from today onwards, but this seems to be as hard as figure drawing. :D

[Whirly]

Cool this thread should be really useful for a lot of people!.

I would also recommend Michael Hamptons exercises. Please see my thread last post for some really badly done ones. http://conceptart.org/forums/showthread.php?t=174888

The ones in particular are number "3 Form-Thru Elipses." "4. Rotating cylanders" And number "5. Combining forms"

I think Dir3t has done some better ones too here http://conceptart.org/forums/showthread.php?t=165378&page=5


What I am planning to do after a few practices is to start to use these exercises from life. Find things that are easily breakon down into geometric shapes and try to draw them that way with correct perspective and proportion. I am going to try it from casts also.

If your geometric shapes are easily constructed in perspective I would assume drawing (constructional rather than optical) becomes a lot easier. Also if you cant do it with cubes and spheres how are you going to be able to do it with biceps and pectorals or the nose on the face. I also believe this 3D drawing rather than optical drawing is the key to being able to draw from the imagination.

Also note as I dont really know how to draw yet so everything above is assumption :)

[Xeon_OND]

Cool this thread should be really useful for a lot of people!.

I would also recommend Michael Hamptons exercises. Please see my thread last post for some really badly done ones. http://conceptart.org/forums/showthread.php?t=174888

The ones in particular are number "3 Form-Thru Elipses." "4. Rotating cylanders" And number "5. Combining forms"

I think Dir3t has done some better ones too here http://conceptart.org/forums/showthread.php?t=165378&page=5


What I am planning to do after a few practices is to start to use these exercises from life. Find things that are easily breakon down into geometric shapes and try to draw them that way with correct perspective and proportion. I am going to try it from casts also.

If your geometric shapes are easily constructed in perspective I would assume drawing (constructional rather than optical) becomes a lot easier. Also if you cant do it with cubes and spheres how are you going to be able to do it with biceps and pectorals or the nose on the face. I also believe this 3D drawing rather than optical drawing is the key to being able to draw from the imagination.

Also note as I dont really know how to draw yet so everything above is assumption :)
Thanks dude, I'll check out your site.

If you're coming from a 3D animation / modeling background, then such stuff will probably be way easier for you as you are used to visualizing stuff in 3D. :)
And yeah, I believe this sort of drawing method is the key to drawing from imagination.
It's like, you sketch a telephone, and then break it into parts, then re-construct the parts from new perspectives. Optical drawing (drawing from life) is probably more for observing how nature works in order to incorporate that into our imaginative works. :D

I wonder if there's a formal term for this sort of drawing method. I tried finding info on Yahoo and Google on this by typing "construction drawing" and "constructive drawing" but all I got was construction of buildings (cement mixers, architectural engineering, tower cranes, apartment materials).

If there was a formal term for this, it'll be easier to find videos and books on this subject. :)

[Whirly]

It might be more traditionally called sculptural drawing (as opposed to optical drawing.

You might find some useful info here on the two trains of though/styles of teaching learning.
http://conceptart.org/forums/showthread.php?t=160487

Vilppu, Hampton, Sheldon Borenstein and the big players here in constructive drawing. I believe it is akin to the renascence style although I could be wrong there.

It requires understanding of the subject rather than just drawing what you see. With that understanding come a greater ability to draw from your imagination and also draw quicker. It however has less emphasis on light and shadow. Constructive drawing is useful for the animator and optical for the portrait drawer. Although everyone will be using both to a varying degree. This is vast over simplification from a novice.

[Slothboy3000]

Speaking of perspective and figure drawing, don't get too technical with it. Bridgeman and Loomis show what it's used for (aligning basic features) but other than that, forshortening and knowledge of the figure will work better than trying to get the muscles to line up to the horizon line. That'll end up with a really stiff figure. Thinking in 3D, as has been said, is essential.
I think it was Michelangelo who said something along the lines of "I think of it as sculpting on the page".

[SweetPea]

great thread and good questions, im trying to get a strong hold on perspective myself atm, and man its tough... good luck! Hey zazers how were you finding the middle of those cubes and rectangular prisms? You drew x's on each of the planes crossing at the middle, but howd u find the middle? and if you wouldnt mind posting that formula for the circle in perspective, i think several of us would appreciate it.

xeon, i think you just need to do a good bit of practice with it. It really a complicated subject, but once you get more familiar with it, it gets a lot easier! id recommend definitely trying those excercises people are posting

[Zazerzs]

hope this helps.

here are a few ways to divide a cube and how to put a 12 point circle into the square.

just in-case the last one is hard to see, I added a larger one, if its too large I'll remove it, meh its too big, ill reformat it. ok, now its long instead of wide.

[FraserMcT]

Wow. I dunno about anyone else, but I find some of the perspective tricks mind blowingly awesome.

[SweetPea]

zazerzs thanks for the really thorough post! i think i understand how to do it for head on views, but what about forshortened sides? how would one find the midpoint of that?

[FraserMcT]

I did a quick animated .gif to show you. It is exactly the same steps. This is why perspective is awesome.
http://i49.tinypic.com/2dvvsck.gif
Zazerz will probably come in here and show you better. I positioned the shape with it's centre near the horizon, so it kinda looks odd.

[Mr_S_14]

I'm attempting to construct a 3d head similar to the method given by Zazers and FraserMCT. It's great information for Plotting points and the proportions rather than guessing.

[FraserMcT]

Here is a better example that I made in 3 point perspective:
http://i47.tinypic.com/2z5272s.gif
I don't think I could ever bore of perspective. I am enjoying this. Does that make me a freak? hahahaha

[George Abraham]

Awesome.

I think the vilppu exercises are also golden.

Overlapping circle's - tangents
Spherical forms - overlap
Square forms
Cylindrical forms, intersecting tubes
Organic squarish/shperical volumes - twists, overlap, elasticity

I think after starting to look at animation that last one could be doubled by studying morphing of simple organic volumes in animation sequences.

I found a new use for a block of post it's. Just staple that bugger.

[SweetPea]

Thanks guys, i spose that thing with the mid points was a bit of a no-brainer... but i apparently had less than no brain at the time haha.. right so i get how to find the mid points now, but in order to find the mid points, ud have to have both end points, and how would i find the end point of a cube thrown into perspective? Imaginitive of course..


say i have a 2 inch cube, then its thrown into 1 point perspective
the frontal face of that cube willl still be 2 inches square.. but the side plane will have the top and bottom lines going to the vanishing point... and the other vertical line will be somewhere closer than 2 inches... but how do i find WHERE? Im about 99.99999% sure that its a formula to do with the angle made with the horizon line... but i dont know what that formula is... any ideas guys?

[FraserMcT]

http://www.sonjebasa.net/Instruction/OnePointPerspective_Cube.pdf
That should answer your question

[FraserMcT]

Is this a cube in 2 point perspective?
http://i50.tinypic.com/r0tu2v.gif
I think it is wrong, but am unsure. It looks wrong, as the side going to the left vanishing point should be shorter? Would appreciate some help.

[Elwell]

Frazer, part of your problem is that you've made the front corner of your box an acute angle. Remember, of you look directly down at a right angle it's 90º, so any foreshortened right angle has to be drawn as obtuse. The front corner of the box you've drawn is actually behind the viewer.

[FraserMcT]

So it's wrong because the vanishing points are too close together?

http://i47.tinypic.com/2z68s2o.gif
Is that correct now?

[Elwell]

No, the problem now is that, since the two sides aren't equally foreshortened, they won't have equal length.

[FraserMcT]

I thought that it was an equal length, but the cube is at an angle?
EDIT: Actually, I get what you mean. The yellow line to get the center of the triangle will mean that the vanishing points would need to be equal distances from the yellow line. How would I draw an angled cube in perspective then?
So much things to think of. It's insane.

[dose]

What are you using to do those animations, FraserMcT?

[FraserMcT]

Photoshop cs3. Quick tutorial on using the tween function in photoshop:
http://i49.tinypic.com/vrdb2p.gif

[dose]

whoa- it's like a meta-photoshop-animation about photoshop animation :headexplode:

That's useful, though- thanks.

[SweetPea]

Good posts guys! Fraser, in your animations after the cubes and vp's are drawn in, a triangle appears.. What is the triangle from and what is it for? Just trying to understand.

Elwell, you said that his problem was since the sides are not equally forshortened, they will not have equal lengths... but how does one find what the lengths WOULD be? I think i know a roundabout way to find it but im not sure..

[George Abraham]

I thought that it was an equal length, but the cube is at an angle?
EDIT: Actually, I get what you mean. The yellow line to get the center of the triangle will mean that the vanishing points would need to be equal distances from the yellow line. How would I draw an angled cube in perspective then?
So much things to think of. It's insane.

Dropping from a plan view is one way that's been shared in a thread here not to long ago.

[FraserMcT]

The triangle is using this idea:
http://fineart.sk/photos/successful_drawing/029.JPG

And the dropping lines from a plan crossed my mind, but the station point confused me until I read this:
http://fineart.sk/photos/successful_drawing/038.JPG

[SweetPea]

Thanks fraser this clears soem things up for me, but ive still a few questions if you dont mind

1) do you find the vanishing points from the station point, or the other way around?
2) How does one select the height to begin the ground plan? is it simply a wherever one wishes?
3) How was the vp of the roof found, and how would one find the other vp for the other side?
and finally
4) How does one know how far below to make the station point?

thanks again sry for the trouble