sample Qt + OpenGL + CUDA example (without camera)

miklos/sample_qt_opengl_cuda_shit_without_camera/glwidget.cpp

+#include "glwidget.h"
+#include "kernel.h"
+
+#include <QGLFunctions>
+#include <cuda_runtime_api.h>
+#include <cuda_gl_interop.h>
+
+GLuint positionsVBO;
+struct cudaGraphicsResource* positionsVBO_CUDA;
+
+GlWidget::GlWidget(QWidget *parent)
+    : QGLWidget(QGLFormat(), parent), func(context()), start(time(NULL))
+{
+}
+
+GlWidget::~GlWidget()
+{
+}
+
+QSize GlWidget::sizeHint() const
+{
+    return QSize(640, 480);
+}
+
+void GlWidget::initializeGL()
+{
+    makeCurrent();
+
+    // Explicitly set device 0
+    cudaGLSetGLDevice(0);
+
+    // Create buffer object and register it with CUDA
+    func.glGenBuffers(1, &positionsVBO);
+    func.glBindBuffer(GL_ARRAY_BUFFER, positionsVBO);
+    size_t size = (size_t)640 * 480 * 4 * sizeof(float); // TODO
+    func.glBufferData(GL_ARRAY_BUFFER, size, 0, GL_DYNAMIC_DRAW);
+    func.glBindBuffer(GL_ARRAY_BUFFER, 0);
+    cudaGraphicsGLRegisterBuffer(&positionsVBO_CUDA, positionsVBO, cudaGraphicsMapFlagsWriteDiscard);
+}
+
+void GlWidget::paintGL()
+{
+    // Map buffer object for writing from CUDA
+    float4* positions;
+    cudaGraphicsMapResources(1, &positionsVBO_CUDA, 0);
+    size_t num_bytes; 
+    cudaGraphicsResourceGetMappedPointer((void**)&positions, &num_bytes,  positionsVBO_CUDA);
+
+    // Execute kernel
+    executeKernel(positions, 640, 480, float(time(0) - start) * 0.1);
+
+    // Unmap buffer object
+    cudaGraphicsUnmapResources(1, &positionsVBO_CUDA, 0);
+
+    // Render from buffer object
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+    func.glBindBuffer(GL_ARRAY_BUFFER, positionsVBO);
+    glVertexPointer(4, GL_FLOAT, 0, 0);
+    glEnableClientState(GL_VERTEX_ARRAY);
+    glDrawArrays(GL_POINTS, 0, 640 * 480); // TODO
+    glDisableClientState(GL_VERTEX_ARRAY);
+}

miklos/sample_qt_opengl_cuda_shit_without_camera/glwidget.h

+#ifndef GLWIDGET_H
+#define GLWIDGET_H
+
+#include <QGLWidget>
+#include <QGLFunctions>
+
+class GlWidget : public QGLWidget
+{
+    Q_OBJECT
+
+public:
+    explicit GlWidget(QWidget *parent = 0);
+    ~GlWidget();
+    QSize sizeHint() const;
+
+protected:
+    void initializeGL();
+    void paintGL();
+
+private:
+    QGLFunctions func;
+    time_t start;
+};
+
+#endif // GLWIDGET_H

miklos/sample_qt_opengl_cuda_shit_without_camera/hello-opengl.pro

+QT += core gui opengl
+CONFIG += debug
+
+TARGET = hello-opengl
+
+TEMPLATE = app
+
+SOURCES += main.cpp glwidget.cpp
+HEADERS += glwidget.h kernel.h
+
+CUDA_SOURCES += kernel.cu
+
+LIBS += -lGLEW -lcuda -lcudart
+
+# Path to cuda toolkit install
+CUDA_DIR      = /usr/
+
+# Path to header and libs files
+INCLUDEPATH  += $$CUDA_DIR/include
+QMAKE_LIBDIR += $$CUDA_DIR/lib
+# GPU architecture
+CUDA_ARCH     = sm_10
+NVCCFLAGS     = --compiler-options -use_fast_math --ptxas-options=-v
+
+CUDA_INC = $$join(INCLUDEPATH,' -I','-I',' ')
+ 
+cuda.commands = $$CUDA_DIR/bin/nvcc -m64 -O3 -arch=$$CUDA_ARCH -c $$NVCCFLAGS $$CUDA_INC $$LIBS  ${QMAKE_FILE_NAME} -o ${QMAKE_FILE_OUT}
+cuda.dependency_type = TYPE_C
+cuda.depend_command = $$CUDA_DIR/bin/nvcc -O3 -M $$CUDA_INC $$NVCCFLAGS ${QMAKE_FILE_NAME}
+cuda.input = CUDA_SOURCES
+cuda.output = ${OBJECTS_DIR}${QMAKE_FILE_BASE}_cuda.o
+
+# Tell Qt that we want add more stuff to the Makefile
+QMAKE_EXTRA_COMPILERS += cuda

miklos/sample_qt_opengl_cuda_shit_without_camera/kernel.cu

+#include "kernel.h"
+
+__global__ void createVertices(float4* positions, float time, unsigned int width, unsigned int height)
+{
+    unsigned int x = blockIdx.x * blockDim.x + threadIdx.x;
+    unsigned int y = blockIdx.y * blockDim.y + threadIdx.y;
+
+    // Calculate uv coordinates
+    float u = x / (float)width;
+    float v = y / (float)height;
+    u = u * 2.0f - 1.0f;
+    v = v * 2.0f - 1.0f;
+
+    // calculate simple sine wave pattern
+    float freq = 4.0f;
+    float w = sinf(u * freq + time)
+        * cosf(v * freq + time) * 0.5f;
+
+    // Write positions
+    positions[y * width + x] = make_float4(u, w, v, 1.0f);
+}
+
+void executeKernel(void *positions_, int width, int height, float time)
+{
+    float4 *positions = (float4 *)positions_;
+    dim3 dimBlock(16, 16, 1);
+    dim3 dimGrid(width / dimBlock.x, height / dimBlock.y, 1);
+    createVertices<<<dimGrid, dimBlock>>>(positions, time, width, height);
+}

miklos/sample_qt_opengl_cuda_shit_without_camera/kernel.h

+#ifndef _KERNEL_H
+#define _KERNEL_H
+
+extern "C" void executeKernel(void *positions_, int width, int height, float time);
+
+#endif // _KERNEL_H

miklos/sample_qt_opengl_cuda_shit_without_camera/main.cpp

+#include <QApplication>
+#include "glwidget.h"
+
+int main(int argc, char *argv[])
+{
+    QApplication app(argc, argv);
+
+    GlWidget w;
+    w.show();
+
+    return app.exec();
+}