Additional details and full source are available at github.com.

This code allows provides an easy to use class that helps users visualize data processed by CUDA kernels. Tested on CUDA 8.0 and OpenGL 4.0, the code should work on modern NVIDIA graphics hardware/software combinations.

Requirements

• An CUDA capable NVIDIA graphics card (See caveats below)
• CUDA Libraries
• OpenGL
• freeglut
• glew
• cmake

Many of these can be installed through your package manager, e.g., apt-get, yum, port, or brew.

Quick Build Directions

mkdir build
cd build
cmake ..
make -j8
./ripple
./julia
./userBuffer

After creating the build directory and running cmake once, you should only need to run make -j8 in the build/ directory if you modify the files.

Writing your own Animation

To write your own animation, follow the general outline provided in the examples ripple.cu, userBuffer.cu, and julia.cu. The primary step is to write an animation function, e.g.,

static void animate_ripple(uchar3 *disp, void *mycudadata);

The first parameter, disp, is a color buffer created automatically by the library on the GPU. The second parameter, mycudadata is a pointer to any user defined struct that provides additional information. The animation function will call a CUDA kernel to write values to the color buffer. After the kernel finishes, the library will display the image to the screen and then call the animation function again in a loop. Due to design limitation of the freeglut library, the animation function needs to be declared static.

The main function simply needs to create a GPUDisplayData object specifying the dimensions of the desired image, a pointer to the user defined data, and a string title.

GPUDisplayData my_display(info.size, info.size, &info, "Ripple CUDA");

To start the animation, call the AnimateComputation method with your new animation function, e.g.,

my_display.AnimateComputation(animate_ripple);

If some code cleanup or post processing of user data needs to happen after closing the window, you can register a clean up function prior to starting the animation:

my_display.RegisterExitFunction(clean_up);

In userBuffer.cu, the user specified data includes additional GPU buffers.

Caveats

CUDA began deprecating older compute architectures in CUDA 7.5. If you are using a new CUDA version with very old NVIDIA GPUs, the CMakeLists.txt may misconfigure your build and result in code that compiles but seems to display white noise instead of a useful image. You can comment out the line

LIST(APPEND CUDA_NVCC_FLAGS "-arch=sm_30")

To use the deprecated architectures, but these will likely be removed in future versions of CUDA. Additionally, more complex examples like julia.cu may run very slowly or not at all on older graphics hardware.

References

This library is inspired by and a simplified form of similar code from the text "CUDA by Example: An Introduction to General-Purpose GPU Programming". This software contains source code provided by NVIDIA Corporation. NVIDIA Copyright headers are retained in code copied verbatim from the book code samples.