Computer Graphics Forum RSS Feed

Coding 2D graphics in C, to be portable

Sun, 28 Jun 2009 11:14:55 -0700

Hello all,

Well, this is my first post in Programmer's Heaven.
Recently, I began developing my own programming library, written in C. When I got to the graphics, I became stumped, because I want the library to be portable, on both OS, and hardware. Every way I think of creating graphics, a different architecture or software platform is excluded. For example, if I used the Windows API, only windows, or possibly Wine can run it; if I use assembler, only one architecture can run it, and I REALLY don't want to re-write the assembly routines for multiple architectures (don't think I could do it for many at all =]...). Any ideas?

Vertical dotted lines running on screen

Thu, 25 Jun 2009 00:24:36 -0700

hi everyone,

the problem i am facing is screen mulfunction. c o l o r e d vertical dotted lines are running on my compaq laptop screen. it just started a week before with just one line which i ignored. then after 2-3 days one more line appeared. next day one more and now 4 lines are there. someone told that lines will go on increasing. what should i do? please help....

Rotation of a 2D image without changing the size

Sat, 20 Jun 2009 04:47:41 -0700

When we use rotation matrix transformation
to rotate a 2D image about a point, the size
of the image changes except for a rotation of
90,180, 270 and 360 degrees. Although
inbuilt function is written in matlab and
photoshop, the size of the image changes
after rotation in boththe softwares.
This is because, the pixel
positions are integer values, and when the
transformation is applied to each and every
piel value of the image, more than one
pixel is transformed to the same position (
because of rounding off)in the rotated image
and hence some of the pixel intensities are
overwitten .
How to overcome this problem?

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convert 3d object to its height field

Thu, 18 Jun 2009 07:07:57 -0700

can anyone give me some suggestions : how to how to convert 3d object to its height field?

thanks a lot

GIF Negative? (Solved)

Sun, 14 Jun 2009 09:49:43 -0700

I am trying to decode a GIF image file format. The GIF file format using LZW can return negative references. If you simply use absolute value on these references you get the "GIF Negative" of the image. The GIF negative is not what I expected. It is not just 255-x to get the back to normal. The best way to describe this is to try adding the color into ms paint (or any other software) and clicking negative with the file format set to GIF. Here is an example.
NORMAL -> Negative
RRR GGG BBB -> RRR GGG BBB
255 000 000 -> 255 204 102
000 255 000 -> 255 204 051
000 000 255 -> 255 153 255
255 255 255 -> 255 153 102
I am trying to convert the "GIF Negative" back to "GIF Normal".
Any ideas of where I could find the answer?

Edit: I found the answer. I will post it here. You can delete this post or save it for future reference.
The way "GIF Negative" works is, after you decode the image but before you reference it, you do this:
if (Current reference)<0
(new reference)=(total references)+(Current reference(should be negative number only!))
Note: Do this after you decode using LZW (if needed).

Get position array following a line

Fri, 12 Jun 2009 06:21:35 -0700

Poll:

	0 votes
	0 votes

I'm trying to do basic GDI animations with bitmaps. What I want to do is make a bitmap move towards a point.
I want the bitmap move in small steps towards this point.
So what I really want to know is how I can get a Point array of all the small steps to this position so I can redraw anything on each position.

I think if I where to make this a function it would have this look. I can't figure out how to make the logic.

Point[] GetLineSteps(Point startxy, Point stopxy)
{

Return LineSteps;
}

Appreciate your help.

how to make this graphic in C++

Sat, 16 May 2009 15:29:50 -0700

i'm training in graphic's programming.
can you help me to make the source code from picture above?
i wanna to learn it.
thanks

OpenGL graphics editor project

Fri, 15 May 2009 00:33:23 -0700

I need the code for a graphics editor using OpenGL...This is part of my engg subject....
Please do send me the code immediately....as its very urgent...

I should be able to run the program in microsoft visual studio...

Please do help me...

viewport to window mapping

Wed, 13 May 2009 20:40:17 -0700

Hi ...
I need to draw a map .I have the latitude longitude values of it .I was able to map these to screen coordinates and then draw the map.Once the map is drawn,as the mouse moves over the map i need to show the latitude and longitude values. This is where i am struck .For the initial case its simple,just rearrangement of window to view port mapping formula .i.e.,
u = (x-xmin)* sx+ umin
v = (y-ymin)* sy + vmin
But once the zoom and pan operations are applied on the map, I dont know how to get the latitude longitude values for each screen coordinate .
If some one knows how to solve this ,Please help me

Thanks in advance

How can i read 3D SOLID in *.dxf files??

Tue, 12 May 2009 15:42:08 -0700

I want to read 3D Solid in dxf/dwg file

This is the code,it is a cilinder

0
3DSOLID
5
154
330
1F
100
AcDbEntity
8
0
100
AcDbModelerGeometry
70
1
1
mnmoo mi m mi
1
ni ^ *+0;:,4 ^ *+0\^ [ nh ^ LR nmqoqnqgmo QK o
1
mjqlffffffffffffff fqfffffffffffffffj:rooh n:rono
1
>,27:>;:- {rn rn _nn mnmqoqnqgmo |
1
=0;& {rn rn {rn {m {rn {rn |
1
3*2/ {rn rn {rn {rn {l {n |
1
,7:33 {rn rn {rn {rn {rn {k {rn {m |
1
9><: {rn rn {rn {j {i {l {rn {h 90-(>-; ,6183: |
1
9><: {rn rn {rn {g {f {l {rn {no 90-(>-; ,6183: |
1
300/ {rn rn {rn {nn {nm {k |
1
<01:r,*-9><: {rn rn {rn kqnkfhioofmlojhoj gqmjkjohffmnfjjkhl kqgmhofgojligofhji o o n no o o n V V o n no 90-(>-; V V V V |
1
9><: {rn rn {rn {rn {nl {l {rn {nk 90-(>-; ,6183: |
1
300/ {rn rn {rn {rn {nj {j |
1
/3>1:r,*-9><: {rn rn {rn kqnkfhioofmlojhoj gqmjkjohffmnfjjkhl o o o rn rn o o 90-(>-;@) V V V V |
1
300/ {rn rn {rn {rn {ni {k |
1
<0:;8: {rn rn {rn {nm {nm {nj {nh -:):-,:; {i {rn |
1
300/ {rn rn {rn {rn {ng {g |
1
/3>1:r,*-9><: {rn rn {rn kqnkfhioofmlojhoj gqmjkjohffmnfjjkhl fqijknfinohlinfjnn o o n n o o 90-(>-;@) V V V V |
1
<0:;8: {rn rn {rn {nj {nj {nm {nh 90-(>-; {f {rn |
1
<0:;8: {rn rn {rn {ni {ni {ng {nf -:):-,:; {nn {rn |
1
:;8: {rn rn {rn {mo o {mo iqmglngjlohnhfjgim {nj {mn 90-(>-; _h *1410(1 |
1
<0:;8: {rn rn {rn {ng {ng {ni {nf 90-(>-; {nl {rn |
1
:;8: {rn rn {rn {mm o {mm iqmglngjlohnhfjgim {ng {ml 90-(>-; _h *1410(1 |
1
):-+:' {rn rn {rn {nh o {mk |
1
:336/,:r<*-): {rn rn {rn kqnkfhioofmlojhoj gqmjkjohffmnfjjkhl o o o rn no o o n V V |
1
):-+:' {rn rn {rn {nf o {mj |
1
:336/,:r<*-): {rn rn {rn kqnkfhioofmlojhoj gqmjkjohffmnfjjkhl fqijknfinohlinfjnn o o n no o o n V V |
1
/061+ {rn rn {rn nkqnkfhioofmlojhoj gqmjkjohffmnfjjkhl o |
1
/061+ {rn rn {rn nkqnkfhioofmlojhoj gqmjkjohffmnfjjkhl fqijknfinohlinfjnn |
100
AcDb3dSolid
350
157

Urgent help Regarding GraphicsEditor using vc++

Sat, 09 May 2009 10:25:06 -0700

I'm doing my engg 6th sem the project is based on Graphics editor, and i'm in need of info regarding this using vc++.
Basic tasks is to create a polygon(finite), create a color box and to fill the color into the created object, ive codes for creation of a polygon and to fill all i need is some additional help on how to make this work altogether.
ive also included a screenshot pls check out the pic,and hoping to hear from u guys asap very urgent.
Thanks

Attachment: kunchathumb.jpg (8643 bytes | downloaded 17 times)

Help with pendulum animation.

Tue, 05 May 2009 08:42:09 -0700

I'm not sure that it's exactly a pendulum. I basically need to animate a necklace that has 6 links connected by an "invisible string". I need the animation to work as the necklace is turned.

As if the person wearing it were doing a cartwheel.

I'm attaching an rough sketch of what i'm talking about.

I just need an algorithm to animate this. I'm not very good with physics and could really use some help. I don't have access to any physics libraries or simulators so I'll actually need to code the whole algorithm.

Attachment: diagram.jpg (12735 bytes | downloaded 32 times)

3D openGL in C++ help wanted

Tue, 28 Apr 2009 11:51:27 -0700

hi, i am trying to do texture mapping and add some smoke with a simple animation to my environment
any tips or links would be appreciated ASAP
if anyone do tasks too contact me if you can work asap thanks

Attachment: Assign3.pdf (157969 bytes | downloaded 48 times)

directdraw scaling problem

Thu, 23 Apr 2009 01:22:37 -0700

Hi all

I'm trying to use directdraw to scale a high mega pixel video to a window size, but I fail on certain video cards.

The details are as followed:
Surface1 holds the original frames, 2144x976, RGB24, offscreen surface, in video memory, not overlayed.
Surface2 is the same just with a different resolution of 704x530.
When I blit from Surface1 to Surface2 the failure occures.
On tested Nvidia/Ati cards it all works fine, but on intel GMA cards I get a not implemented error response.

A few remarks:
1) On smaller source resolutions it all works fine and the scaling works as anticipated
2) Initially this blit caused a blue screen on workstations equipped with the intel cards, but after updating their driver, that was resolved
3) Looking through the card's directdraw capabilities I didn't find any relevant imposed scaling limitations or surface sizes limitations
4) Currently the only work around that I can see for this (without waiting for the blit to fail) is to check for the lack of flag NONLOCALVIDMEM and combine this with a certain resolution threshold above which the surfaces will be created in system memory

Any thoughts?
Thanks in advance

Nir

need help opening protected jpeg

Sat, 11 Apr 2009 14:00:39 -0700

As a visually impaired poker player I usually made some modifications to the graphics of sites that I play on. However on one site (ipoker) when I try to open the graphics files I get an error message from photoshop."unknown or invalid jpeg marker" I downloaded something called xnView but it was unable to open the files. I would be very grateful if someone could tell me how to open the files and then return them to the format they are in once I have altered them.

I know this is possible because there is software available for modifying some of the graphics on the site, unfortunately not the ones I need.

Translating 3D Axis Question

Sat, 11 Apr 2009 11:56:14 -0700

First post...

I am not asking for someone to do my work, rather I am new to the whole 3D coding world and need some general guidelines on how to proceed as well as a primer on the conceptual logic....

Any response would be greatly appreciated...

Background:

I am writing a program that takes output from a CAD program and translates it into real world information usable for the purpose of creating materials estimates for the construction of wood frame buildings.

The CAD program creates a virtual frame of the structure including the studs, plates, headers, jacks, cripples, joists, rafters etc. These are the parts that make up a wood frame building. I am able to export the vector data from the back engine of the cad program as a text file and parse the data into an object oriented library that models the real worlds parts virtually.

The fixed base coordinate system defines the drawing space x axis as 1,0,0 and the y axis as 0,1,0. The z axis is not defined in the the data output and is assumed always through out the the program as 0,0,1. Translated into a real world sense from the viewers perspective, looking away from you is negative Z, looking up is positive Y, and looking right is positive X.

Each entity created has its own transform matrix for x and y, that is to say they have rotational matrix for their positive x and y axis. As an example, if drawing in plan view (looking straight down the y axis), and drawing a line from lower left to upper right on the screen (that would be North East in the real world sense), entity matrix would be x 1,0,-1, and y 0,1,0.

So far this pretty much follows all of the normal programming rules from what I have gathered:

Where I need a little help and guidance is as follows:

Each of the entities (pieces of wood) have rules for their creation that let me apply rules or assumptions to them to extract the relevant data I need to form my materials lists, cutting lists etc.

Without getting into to much detail an example would be that a stud in a wall is always assumed to have the following corresponding relationships: x-axis = thickness, z-axis = width, and y-axis equals height or length.

The CAD output stores all of the data for the polygons that make up the stud in real world coordinates, but unfortunately there is no convention to either the order of the polygons, their lines and the points that make up the lines; its simply a jumble or so it appears. In other words the polygons are not listed like: bottom, top, left face, right face, rear face, front face...they constantly change order.

Bear with me I am almost done....

Here is some sample data of the stud object. This stud is in a wall drawn from South West to North East in a plan view at a 45 degree angle (positive x rotated -45 degrees)...OBJECT st5 is the stud...the data for this stud is broken out into both the entity object and its primitives...

ENTITY:

| +--- BLOCK: fram
| | E-space-base: 8'9_7/8",0',-9'8_7/16"
| | E-space-x: 8_1/2",0',-8_1/2"
| | E-space-y: 0',1',0'
| |
| |--- OBJECT: st5 reflectance:100 gloss:15 diffusion:100
| | E-space-base: 11'7_5/16",1_1/2",-12'5_7/8"
| | E-space-x: 8_1/2",0',-8_1/2"
| | E-space-y: 0',1',0'
| | T-space-base: 8'9_7/8",0',-9'8_7/16"
| | T-space-x: 8_1/2",0',-8_1/2"
| | T-space-y: 0',1',0'

PRIMITIVES:

object: st5
polygon(1) fill-color: 247 r228g207b156
line(2) point1: 11'7_5/16",1_1/2",-12'5_7/8" point2: 11'7_5/16",9'4_1/4",-12'5_7/8"
line(3) point1: 11'7_5/16",9'4_1/4",-12'5_7/8" point2: 11'4_13/16",9'2_1/2",-12'8_3/8"
line(4) point1: 11'4_13/16",1_1/2",-12'8_3/8" point2: 11'4_13/16",9'2_1/2",-12'8_3/8"
line(5) point1: 11'7_5/16",1_1/2",-12'5_7/8" point2: 11'4_13/16",1_1/2",-12'8_3/8"
polygon(6) fill-color: 247 r228g207b156
line(7) point1: 11'8_3/8",9'4_1/4",-12'6_15/16" point2: 11'8_3/8",1_1/2",-12'6_15/16"
line(8) point1: 11'8_3/8",1_1/2",-12'6_15/16" point2: 11'5_7/8",1_1/2",-12'9_7/16"
line(9) point1: 11'5_7/8",9'2_1/2",-12'9_7/16" point2: 11'5_7/8",1_1/2",-12'9_7/16"
line(10) point1: 11'5_7/8",9'2_1/2",-12'9_7/16" point2: 11'8_3/8",9'4_1/4",-12'6_15/16"
polygon(11) fill-color: 239 r128g255b128
line(12) point1: 11'5_7/8",9'2_1/2",-12'9_7/16" point2: 11'4_13/16",9'2_1/2",-12'8_3/8"
line(13) point1: 11'7_5/16",9'4_1/4",-12'5_7/8" point2: 11'4_13/16",9'2_1/2",-12'8_3/8"
line(14) point1: 11'7_5/16",9'4_1/4",-12'5_7/8" point2: 11'8_3/8",9'4_1/4",-12'6_15/16"
line(15) point1: 11'5_7/8",9'2_1/2",-12'9_7/16" point2: 11'8_3/8",9'4_1/4",-12'6_15/16"
polygon(16) fill-color: 247 r228g207b156
line(17) point1: 11'7_5/16",1_1/2",-12'5_7/8" point2: 11'7_5/16",9'4_1/4",-12'5_7/8"
line(18) point1: 11'8_3/8",1_1/2",-12'6_15/16" point2: 11'7_5/16",1_1/2",-12'5_7/8"
line(19) point1: 11'8_3/8",9'4_1/4",-12'6_15/16" point2: 11'8_3/8",1_1/2",-12'6_15/16"
line(20) point1: 11'7_5/16",9'4_1/4",-12'5_7/8" point2: 11'8_3/8",9'4_1/4",-12'6_15/16"
polygon(21) fill-color: 247 r228g207b156
line(22) point1: 11'5_7/8",9'2_1/2",-12'9_7/16" point2: 11'5_7/8",1_1/2",-12'9_7/16"
line(23) point1: 11'5_7/8",1_1/2",-12'9_7/16" point2: 11'4_13/16",1_1/2",-12'8_3/8"
line(24) point1: 11'4_13/16",1_1/2",-12'8_3/8" point2: 11'4_13/16",9'2_1/2",-12'8_3/8"
line(25) point1: 11'5_7/8",9'2_1/2",-12'9_7/16" point2: 11'4_13/16",9'2_1/2",-12'8_3/8"
polygon(26) fill-color: 247 r228g207b156
line(27) point1: 11'8_3/8",1_1/2",-12'6_15/16" point2: 11'7_5/16",1_1/2",-12'5_7/8"
line(28) point1: 11'7_5/16",1_1/2",-12'5_7/8" point2: 11'4_13/16",1_1/2",-12'8_3/8"
line(29) point1: 11'5_7/8",1_1/2",-12'9_7/16" point2: 11'4_13/16",1_1/2",-12'8_3/8"
line(30) point1: 11'8_3/8",1_1/2",-12'6_15/16" point2: 11'5_7/8",1_1/2",-12'9_7/16"

The 3D solid data I have extracted relevant to this stud st5 object comes in as series of 6 polygons each with 4 lines and each line with 2 points stored in real world data. Obviously this is a huge waste of run time memory, so I have taken the data stripped out all redundant information to create a virtual 3D solid with a collection of faces, a collection lines and a collection of points such that I now have 6 faces, 12 lines and 8 points. This of course assumes the solid is a simple 3D rectangle type object.

Finally and why I came here to this forum:

Assuming my stud is a simple rectangular solid, rotated -45 degrees, and that its x-axis = thickness, z-axis = width, and y-axis equals height or length, what would be the most efficient way to extract thickness, width and length?

Catch: The stud may or may not be a simple solid axial planes. The bottom or top cut may hay have a simple bevel or miter, or in fact be a compound cut (that is to say the cut plane shares no axis of the relative coordinate system of its parent solid.

Sorry for the long winded preface...but I thought it necessary to expose as many of my assumptions as possible in hopes thaty flaws in my initial logic might be pointed out and that any responses given are as educational as they are tactical solutions.

I need help with my strategy as much as my tactics...

Thank you....

Carson Wales

Issue of the century: Drawing only what's in the viewport

Tue, 07 Apr 2009 00:47:22 -0700

Hi all. I have a theoretical issue to discuss with you.

As you probably know, user (or world, page, logical etc..) space extents are usually much

larger than device space extents and sometimes, when you have a very large entity (line,

rectangle, whatever) defined in user space and you apply a scale transformation -- the library

doesn't matter here -- to zoom in over a part of the large entity, you reach a point where the

entity disappears (can't be rendered) simply because, at some scale, the transformed vertices

of the entity generate an overflow in device space; but if you zoom in further, you might

encounter some smaller entities in the same spot! I'll try to illustrate better with an

example. Say, our user space supports 64-bit (double) coordinates and our device space is

GDI32 (2^27 units) and we have two lines (in good ol' Cartesian system):

(-100.0, -100.0, +100.0, +100.0) [entity A]

and

(-1000000000000.0, +1000000000000.0, +1000000000000.0, -1000000000000.0) [entity B]

As we can see, the two lines cross point (0, 0) and logically, if I zoom enough to show line A

in my viewport, I should also be able to see (to draw, a programmer may say) line B as well;

but unfortunately, this doesn't happen; when line A is visible, the scaling factor is so big

that the mapped coordinates of line B exceed 27 bits. One solution would be, of course, to

calculate the intersection between line B and my viewport and draw only the visible line

segment. Fine, but what if B was a spline (NURBS), an ellipse, etc. Moreover, periodic curves

can have more than one intersecting segment with the viewport and the formulas and equations

become quite complex. Besides, the idea of down-sampling the user space entity enough to make

it map correctly in device space, flattening it, and finally up-sampling the resulting line

segments, this idea is not acceptable because of the loss of precision (curve smoothness)

incurred..

Let me point out that when the mapped coordinates can't fit in device space, the entity cannot

be flattened (using GDI's FlattenPath()). I tried to flatten (generate) NURBS' using a sample

from the Internet but for some reasons the output doesn't exactly match the same spline when

drawn in AutoCAD(R). Anyway, I wish I knew how to flatten all kinds of curves accurately. My

problem would be solved. I'm trying to study curves intersection now.. damn hard.

All the above applies to Win32. I know little about GDI+ .. but actually, even if the device

space gets larger, the idea of drawing ONLY what's visible in the current viewport (by

generating a new -- usually smaller -- set of sub-entities) should rule IMHO! For performance

reasons and because it simply makes more sense -- and it allows a much broader zooming range

BTW.

So guys! If this has been done before, or if anyone has any clues, books, links.. please let

me know If anyone knows how to generate (by code) an AutoCAD(R) spline accurately, please

help me out :)

In an other forum, I even suggested that this kind of issues (mapping, clamping, clipping..)

should be SOLVED once and for all and become an integral part of all graphics library

packages! Don't you agree?

PS. If anyone knows any other forums or places on the net where I can further discuss these

issues, I would appreciate you letting me know!

Thanks
Robert

movement;

Fri, 03 Apr 2009 22:31:22 -0700

in infix to postfix conversion ;how do i emulate the movement of operators and operands within the stack;my input (a+b*c) is placed in an horizontal cuboid...and my output should be displayed in another horizontal cuboid in its postfix form...

how to play jw file made as .tmp extension???

Wed, 01 Apr 2009 07:47:04 -0700

i was watching a video on net like may be by jw player or by adobe flash player,and found that website making a file xxx.tmp in my temp folder and later it is played in my page.Problem is that file is too long and always remains unfinished ,now i want that the remaining file which had created on my hard disk with extension .tmp i play it as windows media player .but when i changed the extension to wav or mp3 or flv it gives error message ,now is there a way to do this..

Secondly i wonder how that site is converting this tmp file to playing file????

when i opened tmp file in notepad its may be binary code ???

now any suggestions please

opengl:

Sun, 29 Mar 2009 03:47:44 -0700

since i m just a beginner in computer graphics...i find it difficult to write codes for simple geometric shapes which many others say its easy..
so i want a code for 'drawing a stack(vertical cuboidal structure made from cubes placed one above the other, iteratively based on value of 'n'(number of iterations)).. with string "#" placed in its lowermost cube

Attachment: rashmi.zip (465 bytes | downloaded 26 times)

Best language for PostScript output

Wed, 25 Mar 2009 14:03:11 -0700

I've written software for too many years (punched cards in 1970), so I think I can learn just about any language (eventually, grin). I have a bunch of graphics software that I wrote in a language that appears to be dying (TransEra's HiTech BASIC clone of HP's Rocky Mountain Basic). Over the years, I've gotten pretty fluent in PostScript. I've probably re-written half the graphics commands in HTB as my own subs that actually output PostScript correctly <g>. What I'd like to do is to write a new version of that graphics software. What language/environment would you recommend?

Wish list:
* I use vector graphics, not bitmap. This is mandatory. If the language has a way to paint vector graphics on the screen, it would make my life much easier. Final output is PostScript (vector), which I distill to PDF.
* I use very large data sets. I'd like to be able to manipulate arrays of floating-point numbers that have more than 32K elements in a dimension. Being able to perform matrix math is a big plus.
* I tend to use a lot of logarithm/exponential functions, so I don't want something that makes that slow or hard to access (can't imagine that would be a problem with a modern language).
* If possible, I'd rather work under Linux than Windows, but that's not a hard requirement. I'm just getting tired of dealing with BSODs, driver conflicts, etc.
* I want to design the charts myself. I've never seen a packaged routine that does the kinds of things that I want to do, and I'm always thinking of new formats, so an off-the-shelf graphics subroutine package is an unlikely option.

openGL? directX? seriously need help A.S.A.P

Tue, 24 Mar 2009 23:43:53 -0700

I need to present my assignment TOMORROW.
I need to solve mathematical problems using C and also need to add graphic.

I've been planning of writing a program which uses graphic which can take user input,calculate and return the answer as output.

can I do that in openGL with C?

or directX with C?

or is there any other way?

I've spent WEEKS just searching for this.please...................HELP

I'm using Code::Blocks,Windows Vista.

user input openGL with C

Mon, 23 Mar 2009 23:22:33 -0700

how to create an openGL project with C which asks the user to input value and then,do the calculation and return the value as an output?

-thank you-

openGL with c?

Sun, 22 Mar 2009 04:08:48 -0700

hey there,

I'm thinking of solving a math problem in C using openGL graphics.
I tried and it didn't work the way I planned it.
It turned out to be,the answers being displayed in DOS window,and the graphics in openGL window.

I wanna put both of them together in an openGL window.

If this is possible,can anyone please help?

thank you..