A little 3D demo in CC

nitrogenfingers, on 17 June 2013 - 01:56 AM said:

Don't get excited, this isn't anything terribly fancy, just moving around 3D-translated points:

KingOfNoobs, on 18 June 2013 - 01:14 AM said:

This is awesome! But how have you learned all the stuff for this?

wilcomega, on 17 June 2013 - 09:02 AM said:

Amazing. when textures will be avalible iw ill make an FPS :3

local col = world[i].color

for i,vertex in ipairs(world) do
				    --Applying camera space
				    world[i] = global:apply(vertex)
		    end

		    for i,vertex in ipairs(world) do
				    local vect = global:apply(vertex)
				    local col = vect.color
                    
				    world[i] = graphics.project(vect)
				    --Here until we sort out depth buffering
				    world[i].color = model.colors[i]
				    world[i].dist = distances[i]
		    end

KingOfNoobs, on 18 June 2013 - 01:14 AM said:

But how have you learned all the stuff for this?

SuicidalSTDz, on 17 June 2013 - 08:24 PM said:

A god amongst men, nitrogenfingers is he.

nitrogenfingers, on 17 June 2013 - 10:31 PM said:

Spoiler

What on earth is that mess of pixels? It's the same cube as above but with all the faces filled in, in no particular order! Depth buffering and face culling is the next job, neither of which hopefully will be too challenging. From there I'll have to come up with some strategy to managed the jagged edges, that I've yet to really sort out.

Spoiler

Spoiler

billysback, on 18 June 2013 - 07:59 AM said:

also, some of your code makes no sense…

local col = world[i].color

is not used, not only is the variable "col" not used but world is never ever given a variable called "color", not until after the loop is finished and world is replaced, at least.

[…]

also I'm not 100% sure on the usage of this loop

for i,vertex in ipairs(world) do
					--Applying camera space
					world[i] = global:apply(vertex)
			end

I'm kinda tired right now, but surly you could do

			for i,vertex in ipairs(world) do
					local vect = global:apply(vertex)
					local col = vect.color
					
					world[i] = graphics.project(vect)
					--Here until we sort out depth buffering
					world[i].color = model.colors[i]
					world[i].dist = distances[i]
			end

and save it looping through the table once too many times.

billysback, on 18 June 2013 - 07:59 AM said:

also, some of your code makes no sense…
[…]
I'm not trying to be mean and nit-pick, I was just trying to play around with it and getting confused as hell. Sorry :P/>

Bubba, on 24 June 2013 - 10:46 PM said:

Maybe I'll have to wait for college to really get into this, but if you've got any recommendations as to where I can get started I would be forever grateful :)/>

nitrogenfingers, on 24 June 2013 - 11:26 PM said:

-snip-

--getTriangle() returns a table containing the points of a hollow triangle
--fillTriangle() fills this triangle and returns a similar table
--drawShape() handles these "shape" tables and draws them with the background colour, text colour and text you define.
drawShape(fillTriangle(getTriangle({x1, y1}, {x2, y2}, {x3, y3})), colors.red, colors.black, " ")

--there is also a fillSquare method which to draw would simply be:
drawShape(fillSquare({x1, y1}, {x2, y2}, {x3, y3}, {x4, y4}), colors.red, colors.black, " ")

--xn and yn are the x coordinates of the the point n, e.g. point one is {x1,y1} where x1 is the x coordinate of point 1 and
--y is the y cooridinate point point 2
--in fillSquare the points must be in order around the square, the order doesn't matter as long as a point is not followed
--by an opposite point.
--so:
fillSquare({1,1},{1,2},{2,2},{2,1}) --is valid
fillSquare({1,1}{1,2}{2,1},{2,2} --is NOT valid
--because triangles only have 3 points this doesn't matter

-- This code render a quad on the screen

gl:matrixMode('PROJECTION')
gl:loadIdentity()
gl:perspective(60, WIDTH/HEIGHT, 0, 100)

gl:matrixMode('MODELVIEW')
gl:loadIdentity()

gl:scale(scale)
gl:rotate(rotateX,  1,  0,  0)
gl:rotate(rotateY,  0,  1,  0)
gl:rotate(rotateZ,  0,  0,  1)
gl:translate3(translate)
gl:_begin('TRIANGLES')
gl:color(graphics.colors.red)
gl:vertex3(vector.new(-1.0, -1.0, 1.0))

gl:color(graphics.colors.red)
gl:vertex3(vector.new(1.0,  1.0,  1.0))

gl:color(graphics.colors.red)
gl:vertex3(vector.new(-1.0, 1.0,  1.0))

gl:color(graphics.colors.green)
gl:vertex3(vector.new(1.0,  -1.0, 1.0))

gl:color(graphics.colors.green)
gl:vertex3(vector.new(1.0,  1.0,  1.0))

gl:color(graphics.colors.green)
gl:vertex3(vector.new(-1.0, -1.0, 1.0))

gl:_end()

Engineer, on 17 June 2013 - 06:35 PM said:

First something like 3dmaze

Mads, on 18 June 2013 - 03:13 AM said:

wilcomega, on 17 June 2013 - 09:02 AM said:

Amazing. when textures will be avalible iw ill make an FPS :3

Implement them yourself. If you cannot do that, you have literally 0 chance of creating a 3D FPS game.

Pinkishu, on 30 June 2013 - 03:32 PM said:

Mads, on 18 June 2013 - 03:13 AM said:

wilcomega, on 17 June 2013 - 09:02 AM said:

Amazing. when textures will be avalible iw ill make an FPS :3

Implement them yourself. If you cannot do that, you have literally 0 chance of creating a 3D FPS game.

How does that make any sense? You don't have to know how the graphics engine you use works internally in order to make a game with it.

Hellkid98, on 09 July 2013 - 06:52 AM said:

Great work nitro!
Just saw your new video and I was simply amazed! :)/>

Also, Are you going to try to make circles next?
Like earth or something :3

KingOfNoobs, on 09 July 2013 - 09:27 AM said:

Hellkid98, on 09 July 2013 - 06:52 AM said:

Great work nitro!
Just saw your new video and I was simply amazed! :)/>

Also, Are you going to try to make circles next?
Like earth or something :3

Circles in games are often just lots of triangels

Hellkid98, on 09 July 2013 - 06:52 AM said:

Great work nitro!
Just saw your new video and I was simply amazed! :)/>

Also, Are you going to try to make circles next?
Like earth or something :3

Hellkid98, on 09 July 2013 - 06:52 AM said:

Also, Are you going to try to make circles next?
Like earth or something :3

nitrogenfingers, on 10 July 2013 - 07:27 PM said:

I am indeed planning to try making planets- this I'll do by producing a UV Sphere , which you can think of as a sphere segmented into square faces.

The one example I know of making 3D circles or at least curvature is by Bezier lines. I may actually give this a go- no idea how it'll turn out in CC of all things but it may be cool. After all, it looked great in this game:

gamax92, on 12 July 2013 - 01:55 AM said:

Even at super resolution, it does run smoothly and at a full 20fps. I did my initial port in actual minecraft and it ran pretty good. There are still a few issues (atleast when i gave ds84182 the code) to be worked out but so far it looks pretty nice.

Hellkid98, on 09 July 2013 - 06:52 AM said:

Great work nitro!
Just saw your new video and I was simply amazed! :)/>/>

Also, Are you going to try to make circles next?
Like earth or something :3

nitrogenfingers, on 10 July 2013 - 07:27 PM said:

Hellkid98, on 09 July 2013 - 06:52 AM said:

Also, Are you going to try to make circles next?
Like earth or something :3

I am indeed planning to try making planets- this I'll do by producing a UV Sphere , which you can think of as a sphere segmented into square faces.

The one example I know of making 3D circles or at least curvature is by Bezier lines. I may actually give this a go- no idea how it'll turn out in CC of all things but it may be cool. After all, it looked great in this game:

Atarian, on 16 August 2013 - 02:18 AM said:

What game is that?

Atarian, on 16 August 2013 - 02:14 AM said:

Hellkid98, on 09 July 2013 - 06:52 AM said:

Great work nitro!
Just saw your new video and I was simply amazed! :)/>/>

Also, Are you going to try to make circles next?
Like earth or something :3

Dont you mean spheres?

nitrogenfingers, on 10 July 2013 - 07:27 PM said:

Hellkid98, on 09 July 2013 - 06:52 AM said:

Also, Are you going to try to make circles next?
Like earth or something :3

I am indeed planning to try making planets- this I'll do by producing a UV Sphere , which you can think of as a sphere segmented into square faces.

The one example I know of making 3D circles or at least curvature is by Bezier lines. I may actually give this a go- no idea how it'll turn out in CC of all things but it may be cool. After all, it looked great in this game:

What game is that?

Nasso, on 14 June 2015 - 03:43 PM said:

I saw your 3D demo, it's awesome ! But how do you convert 3D vector (x, y, z) to 2D screen coordinates (x, y) ? I know how to do transform with a matrix, but how to display 3D vectors on screen ? Thanks!

nitrogenfingers, on 17 June 2015 - 03:09 AM said:

Yeah it uses term.write as everything does (or did). Blitting may well speed the program up, but the issue with this engine at least was not so much speed but a few deficiencies in implementation like the inability to properly render intersecting faces, culling that doesn't take projection into account, long inner frustrum length and so on. I think other programs have been developed or are in development that will overcome these issues, and though I keep intending to go back and update this code, I haven't yet managed.

nitrogenfingers, on 16 June 2015 - 12:04 PM said:

There are a few different methods. I just do a simple shearing calculation to make it 'look' like it's in perspective because it's cheap and works for simple applications, but isn't recommended for more complex scenarios. A better approach is to use what's called a 'projection matrix', which modifies the points according the aperture and lens width of your camera.

My cheap little method is in the 'render' source code file. You can find equations for orthographic and perspective matrices to get your vectors into projected space here: http://www.codinglabs.net/article_world_view_projection_matrix.aspx

1, 0, 0, 0
0, 1, 0, 0
0, 0, 1, 0
x, y, z, 1

1, 0, 0, x
0, 1, 0, y
0, 0, 1, z
0, 0, 0, 1