diff options
| -rw-r--r-- | balls.c | 29 |
1 files changed, 20 insertions, 9 deletions
@@ -80,6 +80,7 @@ void keyboard(unsigned char key, int x, int y); void move(void); void collideBalls(void); cl_event collideWalls(void); +void copyPositionsToGpu(cl_event cpuEvent); void genVertices(void); void freeCL(void); void freeGL(void); @@ -534,27 +535,23 @@ setKernelArgs(void) { void animate(int v) { cl_event cpuEvent; - int err; clock_t tstart, elapsed; unsigned int nextFrame; tstart = clock(); + /* Start computing next frame on CPU. */ move(); collideBalls(); cpuEvent = collideWalls(); + /* Disply current from with GPU. */ display(); - /* Copy new positions to GPU. */ - err = clWaitForEvents(1, &cpuEvent); - if (err < 0) - sysfatal("Error waiting for CPU kernel to finish.\n"); - clReleaseEvent(cpuEvent); - err = clEnqueueWriteBuffer(gpuQueue, positionsGpuBuf, CL_TRUE, 0, nBalls*2*sizeof(float), positionsHostBuf, 0, NULL, NULL); - if (err < 0) - sysfatal("Failed to copy positions from host to GPU.\n"); + /* Copy next frame's positions from CPU to GPU. */ + copyPositionsToGpu(cpuEvent); + /* Display next frame. */ elapsed = (clock() - tstart) / (CLOCKS_PER_SEC / MS_PER_S); nextFrame = (elapsed > FRAME_TIME_MS) ? 0 : FRAME_TIME_MS-elapsed; glutTimerFunc(nextFrame, animate, 0); @@ -627,6 +624,20 @@ collideWalls(void) { return event; } +/* Wait for the CPU to finish computing the new positions and then copy them to the GPU. */ +void +copyPositionsToGpu(cl_event cpuEvent) { + int err; + + err = clWaitForEvents(1, &cpuEvent); + if (err < 0) + sysfatal("Error waiting for CPU kernel to finish.\n"); + clReleaseEvent(cpuEvent); + err = clEnqueueWriteBuffer(gpuQueue, positionsGpuBuf, CL_TRUE, 0, nBalls*2*sizeof(float), positionsHostBuf, 0, NULL, NULL); + if (err < 0) + sysfatal("Failed to copy positions from host to GPU.\n"); +} + void genVertices(void) { int err; |