Opengl and directx for java or c++ or Java3D

Question

I am new to the 3D programming and I have many queries and I hope those expect can answer me. Thank you very much.
I have some experience in writing directx 7.0 in C++. I find that the IDirect3DDevice7 in directx7.0 does not support 256 colors but direct3ddevice in directx5.0 does.
However, the direct3ddevice in directx5.0 in 16 or 32 bit color performs very strange. Distortion is found in displaying a 3D image.
1.     Do you have this experience? Does direct3ddevice in directx5.0 not work in 16 or 32 bit colors?
2.     If I want to write a 3D directx program in C++ that can be work in every resolution, what can I do?
3.     Can opengl work in every resolution 256 colors, 16, 32 bits?
4.     Does opengl work in every platform?
5.     Can I write an opengl program in window platform and run it in Linux without any modification or compilation ?
6.     Does the opengl runtime different from platform to platform ?
7.     If I deploy an opengl progam, do I need to deploy the runtime for a particular platform with it.
8.     Opengl is claimed to be open source. What does it mean ? Can I modify the code of the opengl sdk or runtime and re-complie it and make it my own version of opengl ?
9.     I find many version of opengl sdk in the web. Some is special to a particular hardware eg. NVIDIA. Some is not bounded to any hardware. What is the different between them ? How can I choose from them ?
10.     I know that there is directx for java and opengl for java. Is it the so called java 3D ?
11.     Does opengl or directx together with Java2 become Java 3D ?
12.     However I cannot find any directx code or directive for importing the directx package in the Java 3D sample code.
13.     Does the Javax provide the utility for 3D programming by hiding the 3D device or texture surface creation ?
14.     I find some code segment from MSDN which shows the way to create a directdraw object in an applet. I wonder what is the proper way to use directx or opengl in java since my main goal is to create a directx application that can be worked in the web.
15.     Lastly, from my understanding, directx is a com api which can be used in every programming languages. Does it imply that with a directx sdk, I can write a directx application in C++, java, or vb ?
16.     But, I find that the code to do the same task in the three programming languages is very different. The object creation methods, the data structure for directx in the three programming languages is different. Is the same sdk realy used in different programming languages ? The object name for e.g. direct3ddevice is different from vb (Direct3DDevice7) and c++ (IDirect3DDevice7).

Answer 1

I'm no expert in 3D graphics programming, but I have some experience. I'll try to answer some of your questions.
2.     If I want to write a 3D directx program in C++ that
can be work in every resolution, what can I do?I think both DirectX and OpenGL supports any resolution and color depth. It's more a matter of which resolutions your graphics driver supports.
3.     Can opengl work in every resolution 256 colors, 16,
32 bits?Yes.
4.     Does opengl work in every platform?OpenGL is available on many platforms. Look at GL4Java if you want to use OpenGL in Java, it's available on many platforms. Look at: http://www.jausoft.com/gl4java.html
5.     Can I write an opengl program in window platform
and run it in Linux without any modification or
compilation ?Yes, if you write it in Java. In C++ you will need to recompile the app.
6.     Does the opengl runtime different from platform to
platform ?No, it's a standard. There are some extensions that are driver dependant, but if you stick to the standard it will run unmodified on all platforms.
7.     If I deploy an opengl progam, do I need to deploy
the runtime for a particular platform with it.I don't think OpenGL is available by default on all platforms.
8.     Opengl is claimed to be open source. What does it
mean ? Can I modify the code of the opengl sdk or
runtime and re-complie it and make it my own version
of opengl ?OpenGL is not open source. OpenGL is a standard, it can't be open source since there is no source code.
9.     I find many version of opengl sdk in the web. Some
is special to a particular hardware eg. NVIDIA. Some
is not bounded to any hardware. What is the different
between them ? How can I choose from them ?If you have modern graphics card the driver includes support for OpenGL on MS Windows. For Linux you use Mesa I think. See GL4Java homepage for more info.
10.     I know that there is directx for java and opengl
for java. Is it the so called java 3D ?GL4Java implements the OpenGL functions in Java. Java3D is a high level API that runs on either OpenGL or DirectX.
11.     Does opengl or directx together with Java2 become
Java 3D ?No. The Java3D package is available for download at java.sun.com.
12.     However I cannot find any directx code or
directive for importing the directx package in the
Java 3D sample code.You can't call DirectX directly in Java3D. It hides the underlying layers.
13.     Does the Javax provide the utility for 3D
programming by hiding the 3D device or texture surface
creation ?Java3D is platform independent and hides things like the hardware, drivers etc.
14.     I find some code segment from MSDN which shows the
way to create a directdraw object in an applet. I
wonder what is the proper way to use directx or opengl
in java since my main goal is to create a directx
application that can be worked in the web.I dont know if DirectX is available for Java. I recommend that you use OpenGL instead, or Java3D if you want an easy, high level API.
15.     Lastly, from my understanding, directx is a com
api which can be used in every programming languages.
Does it imply that with a directx sdk, I can write a
directx application in C++, java, or vb ?In C++ and VB, yes. Dont know if there are any Java DirectX bindings available.
16.     But, I find that the code to do the same task in
the three programming languages is very different. The
object creation methods, the data structure for
directx in the three programming languages is
different. Is the same sdk realy used in different
programming languages ? The object name for e.g.
direct3ddevice is different from vb (Direct3DDevice7)
and c++ (IDirect3DDevice7).Don't mix programming languages in the same app. Decide if Java or C++ is the right language for you, then use the tools available for the language you choose.
My recommendation is to go for Java and Java3D if you are inexperienced with 3D graphics programming. Use Java + OpenGL if you know about vertices, textures, transforms etc.