Cool.

Do you need the

vec4 Translate();

prototype at the top of vertex shader 1?

Is there a compiler error if you omit it?

Ooh, right, so instead of inlining functions other than 'main' in a single shader object, you separate them (hence allowing code sharing) into different source files and hence different shader...

Hi,

This one has been bugging me for a while now. In the GL_ARB_shader_objects spec, under 2.14.2 Program Objects, it says

----
It is permissible to attach multiple shader objects of the same...

Certainly do.

I should have said that the FPS I'm getting are in the order of 600-700FPS so that kinda rules out vsync issues.

[This message has been edited by markfcsl (edited 11-18-2003).]

Hi,

I'm seeing a performance issue with the buffer flipping mode selection on these drivers. This only seems to happen in full screen modes.

If I choose "auto select" (which the tooltip help...

I agree with sqrt that 3D labs do have some nice drivers for their Wildcat range, and they have become a lot more stable (at least from my point of view). Their developer relations are also very...

OK, so just to confirm, can we expect any data preservation when you call MapBuffer or not?

I just did a *very* quick test, inserting a BufferDataARB command with a NULL data pointer before my MapBuffer, as suggested by CybeRUS.

It's not a heavy-weight example, just morphing geometry (so...

Cass,

So the approach I've taken, where I can possibly map the same VBO more than once per frame, and expect the data to be there, is inherently flawed?


Mark

OK, so ignore this post now... it did turn out to be my use of VBOs.

My test data that was failing contained static color and texture coordinates, as well as dynamic positions and normals, but I...

OK, so I just did the obvious thing and looked at the memory at the pointer returned by MapBuffer under a debugger. This may be an unfair test as it's not running in realtime anymore, but heck.
...

Yes. It never returns GL_FALSE. If it does, I send out a debug message and then respecify the VBO with a NULL pointer data to glBufferDataARB, but I've never seen that happen.

I should say that...

In my VBO code, I generate 4 ARRAY_BUFFER VBOs of 256Kb each, which I use to stream dynamic vertex data into. I set these up with GL_STREAM_DRAW_ARB usage.

I don't know what the new vertex data is...

Anyone know if there are any good ones available "out there" for both fullscreen and windowed applications?

Preferrably without GLU/GLUT... I'm interested in the bare AGL & GL.

I've looked at...

I'm also seeing lower performance using VBO on GeForce4 Ti hardware, and with just static geometry, than with VAR. (with an ATI Radeon 9700 Pro, VBO just flies faster than VAO ...

OK, it was my test app that was wrong. You can read compressed cubemap faces back from the GL.

It was using a multitextured geometry, with the cube map in texunit1, and another similar texture in...

Suppose you have support for GL_ARB_texture_compression, GL_ARB_texture_cube_map, GL_EXT_texture_compression_s3tc.

Is it valid to get the compressed faces back from the GL using
...

Do'h. You got it.

I wasn't reading the last 1x1 mipmap, so I guess it was reading incorrectly offset data from the dds file from the NEGATIVE_X offset onwards.

Cheers!

Hi,

I've just tried implementing cubemap support by reading from a DDS file (they are DXT1 compressed).

According to the DDS specifications for cubemaps, the faces each appear with their...

Hi,

If my OpenGL application is running in a 16bpp pixel format, I would create my textures in a 16bpp format, e.g. GL_RGBA4, to not hog the bandwidth by moving texture data I won't be using.
...

I looked into this a few months ago but found it didn't do anything for performance. I've also had other colleagues say the same.

I queried with ATI and their response was that the extension spec...

Ah yes, I'd not taken the queue into account.

I'll have to have a rethink about how to test performance.

Has anyone had any experience analysing the performance of OpenGL functions?

Intel's VTune is very useful to find CPU bottlenecks, but it would be nice to be able to do something similar with the...

Well, turned out it was my problem throughout http://www.opengl.org/discussion_boards/ubb/smile.gif

The partially scrambled vertex positions was due to bad initialization data. This did not occur...

So is your render function something along the lines of, say,

glBindBufferARB( GL_ELEMENT_ARRAY_BUFFER_ARB, indexBuffer);

glBindBufferARB( GL_ARRAY_BUFFER_ARB, staticBuffer1);
gl*Pointer( ......