A simple 3D render method

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Posts: 26
Joined: Aug 01, 2007 10:05

A simple 3D render method

Postby AndT » Jan 10, 2008 20:08

Over 100 FPS (ca. 300-600) and highres ;)

Code: Select all

' A simple 3D demo written by AndT

type xycor
    x as double
    y as double
end type

type polygon
    p1 as xycor
    p2 as xycor
    p3 as xycor
end type

dim as polygon poly(1 to 2)

sub drawpolygon(byval p1 as xycor,byval p2 as xycor,byval p3 as xycor,byval col as uinteger)
    line (p1.x,p1.y)-(p2.x,p2.y),col
    line (p2.x,p2.y)-(p3.x,p3.y),col
    line (p3.x,p3.y)-(p1.x,p1.y),col
end sub

'Main programm


screenres resx,resy,,,1
dim as integer mode,mode2,mode3,mode4,mode5,mode6,mode7,mode8


' Main loop

' Draw
drawpolygon (Poly(1).p1,Poly(1).p2,Poly(1).p3,15) ' Polygon1
drawpolygon (Poly(2).p1,Poly(1).p2,Poly(1).p3,15) ' Polygon2

sleep 1,1 ' remove this to see the real FPS xD

' Remove
drawpolygon (Poly(1).p1,Poly(1).p2,Poly(1).p3,0) ' Polygon1
drawpolygon (Poly(2).p1,Poly(1).p2,Poly(1).p3,0) ' Polygon2

' Simple Animation Code ;)
if poly(1).p1.x > resx then mode2 = 0
if poly(1).p1.x < 1 then mode2 = 1
if poly(1).p2.y > resy then mode3 = 0
if poly(1).p2.y < 1 then mode3 = 1
if poly(1).p2.x > resx then mode4 = 0
if poly(1).p2.x < 1 then mode4 = 1
if poly(1).p1.y > resy then mode5 = 0
if poly(1).p1.y < 1 then mode5 = 1
if poly(1).p3.x > resx then mode6 = 0
if poly(1).p3.x < 1 then mode6 = 1
if poly(1).p3.y > resy then mode7 = 0
if poly(1).p3.y < 1 then mode7 = 1
if poly(2).p1.x > resx then mode = 0
if poly(2).p1.x < 1 then mode = 1
if poly(2).p1.y > resy then mode8 = 0
if poly(2).p1.y < 1 then mode8 = 1
if mode = 1 then poly(2).p1.x + = 1 else poly(2).p1.x - = 1
if mode2 = 1 then poly(1).p1.x + = 2 else poly(1).p1.x - = 2
if mode3 = 1 then poly(1).p2.y + = 3 else poly(1).p2.y - = 3
if mode4 = 1 then poly(1).p2.x + = 2 else poly(1).p2.x - = 2
if mode5 = 1 then poly(1).p1.y + = 1 else poly(1).p1.y - = 1
if mode6 = 1 then poly(1).p3.x + = 2 else poly(1).p3.x - = 3
if mode7 = 1 then poly(1).p3.y + = 2 else poly(1).p3.y - = 2
if mode8 = 1 then poly(2).p1.y + = 1 else poly(2).p1.y - = 1

frame += 1
  IF frame >= 50 THEN
    FPS = INT(frame / (TIMER - t))
    t = TIMER
    frame = 0
    locate 2,2
    print "FPS : ";FPS
    end if
loop until inkey <> ""
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Postby notthecheatr » Jan 10, 2008 21:27

It only compiles with -lang deprecated :P

Well not bad, but it doesn't really do a whole lot. Drawing wireframe is one thing. drawing shaded models is entirely different (due to the complications raised by HSR and other things - and if you want proper lighting, materials, and texturing - forget about it in real time.) Nice example, but in the end for real 3d OpenGL or DirectX are pretty much the best options.
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Postby elsairon » Jan 10, 2008 22:04


Add texture support for the poly's and non visible poly culling you're set ... :P
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Postby notthecheatr » Jan 10, 2008 22:09

That's not a very simple thing to do, besides as I said by the time he does that the FPS will plummet.
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Postby 1000101 » Jan 11, 2008 1:51

I don't know why people insist on doing 3d in software anymore.

Welcome to 1993.
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Postby Mysoft » Jan 11, 2008 2:50

year 2057: "we need to make a new graphic card... but no one in the world remember how to program the 3D software for the graphic card..."

maybe this can be a reason... (the same with ASM), i guess in my opinion forget those things only will make a few BAD try to control people knowing those things that everyone else dont care to know... (welcome to matrix)...

ofcourse that is a Exaggeration, but in a scale of time... it's clearly true... (gladly we have books and... storage devices... but... this happened before)
Site Admin
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Postby counting_pine » Jan 11, 2008 3:25

1000101 wrote:I don't know why people insist on doing 3d in software anymore.
There are people who like to mess around with ideas and algorithms, to get to know their way around basic concepts and build up their knowledge around them.
There are also people who prefer to maximise what they can accomplish, by using established ideas and methods. They're not as interested in "how does it work?", so much as "how can I use it?"
Both are perfectly acceptable schools of thought, but without the former, there wouldn't be the latter.
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Postby redcrab » Jan 18, 2008 14:59

Sorry but I do not see anything in 3D ...
Just bouncing tied lines ...

Did I miss something ???
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Location: Texas

Postby dabooda » Jan 18, 2008 15:25

You didn't miss anything, there is no 3-d there. Just some tied lines with pong bouncing ends. There is not rotation, scale or rather perspective here. This is not 3-d, just an optical illusion if even that. The only true thing shown here is how to draw a triangle. I was wondering why your DrawPolygon() routine isn't set up where you simply pass a pointer to your polygon instead of feeding all 3 corners?

Code: Select all

'DrawPolygon Sub
Sub drawpolygon( poly as polygon ptr, col as UInteger)
     Line (poly->p1.x, poly->p1.y)-(poly->p2.x, poly->p2.y), col
     Line (poly->p2.x, poly->p2.y)-(poly->p3.x, poly->p3.y), col
     Line (poly->p3.x, poly->p3.y)-(poly->p1.x, poly->p1.y), col
End Sub

'To call it simply do this
drawpolygon @poly(0), 15
drawpolygon @poly(1), 15

You could probably even set it up to pass the polygon by reference, anything is better than feeding it each corner. That kind of defeats the purpose of setting it up as a type.

DaBooda out...
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Postby vdecampo » Jan 18, 2008 16:08

It is what it is. I don't understand the harsh criticism. This wasn't advertised as a new 3D rendering system. Just a very simple raster gfx example. Jeez!

Thanks for the submission AndT. I'm sure some will find it intersting.

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Postby Dr_D » Jan 18, 2008 22:40

I also think that doing 3d in software mode is excellent practice and keeps your math skills sharp. Also, it's just plain fun. I think most people that do neat things with hardware accelerated libraries, like OpenGL or DirectX, have some background in software rendering.

Speaking of software...
Now for the obligatory FBEXT reference! :D We've recently added a flat shaded triangle primitive rendering function, and I made a demo using it. You can hit space to toggle vsync... and that's pretty much it.

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Postby dabooda » Jan 19, 2008 0:17

'A Simple 3D Render Method' implies that it is 3D, which it is not. That isn't criticism but rather pointing out a fact. It simply needs to be renamed.

I also agree doing software 3d is essential for anyone wishing to program 3d with hardware. Not to mention its just fun. Who cares if it is nowhere near today's standards. I'm more impressed with someone who renders a shaded polygon with code, than simply feeding a description to HAL.

DaBooda out...
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Postby D.J.Peters » Jan 19, 2008 8:57

hello Dr_D
nice example but why are the fps so low?

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Postby DaveUnit » Jan 19, 2008 14:00

awesome example Dr_D. FB Ext is really cool.
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Postby dabooda » Jan 19, 2008 14:14

I was being critical earlier and I apologize, don't want to come off like some around here. It was counter productive and again I apologize.

If you are interested in software 3d I can recommend a great book: Flights of Fantasy by Christopher Lampton. Its main concept is the building of a flight simulator and the code snippets are in c. But it is an excellent source and teaches you about 3d rendering from the ground up. Good Stuff.

DaBooda out...

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