diff options
Diffstat (limited to 'libdimension')
| -rw-r--r-- | libdimension/dimension/raytrace.h | 2 | ||||
| -rw-r--r-- | libdimension/raytrace.c | 129 |
2 files changed, 116 insertions, 15 deletions
diff --git a/libdimension/dimension/raytrace.h b/libdimension/dimension/raytrace.h index b58a39b..2be79a8 100644 --- a/libdimension/dimension/raytrace.h +++ b/libdimension/dimension/raytrace.h @@ -25,7 +25,7 @@ #ifndef DIMENSION_RAYTRACE_H #define DIMENSION_RAYTRACE_H -void dmnsn_raytrace_scene(dmnsn_scene *scene); +int dmnsn_raytrace_scene(dmnsn_scene *scene); dmnsn_progress *dmnsn_raytrace_scene_async(dmnsn_scene *scene); #endif /* DIMENSION_RAYTRACE_H */ diff --git a/libdimension/raytrace.c b/libdimension/raytrace.c index aa3a445..d634747 100644 --- a/libdimension/raytrace.c +++ b/libdimension/raytrace.c @@ -26,17 +26,20 @@ typedef struct { dmnsn_progress *progress; dmnsn_scene *scene; + + /* For multithreading */ + unsigned int index, threads; } dmnsn_raytrace_payload; /* Thread callback */ static void *dmnsn_raytrace_scene_thread(void *ptr); /* Raytrace a scene */ -void +int dmnsn_raytrace_scene(dmnsn_scene *scene) { dmnsn_progress *progress = dmnsn_raytrace_scene_async(scene); - dmnsn_finish_progress(progress); + return dmnsn_finish_progress(progress); } /* Raytrace a scene in the background */ @@ -68,9 +71,8 @@ dmnsn_raytrace_scene_async(dmnsn_scene *scene) return progress; } -/* Actual raytracing implementation */ -static void dmnsn_raytrace_scene_impl(dmnsn_progress *progress, - dmnsn_scene *scene); +/* Start the multi-threaded implementation */ +static int dmnsn_raytrace_scene_multithread(dmnsn_raytrace_payload *payload); /* Thread callback */ static void * @@ -79,17 +81,111 @@ dmnsn_raytrace_scene_thread(void *ptr) dmnsn_raytrace_payload *payload = ptr; int *retval = malloc(sizeof(int)); if (retval) { - dmnsn_raytrace_scene_impl(payload->progress, payload->scene); - *retval = 0; + *retval = dmnsn_raytrace_scene_multithread(payload); } dmnsn_done_progress(payload->progress); free(payload); return retval; } +/* Thread callback */ +static void *dmnsn_raytrace_scene_multithread_thread(void *ptr); + +/* Set up the multi-threaded engine */ +static int +dmnsn_raytrace_scene_multithread(dmnsn_raytrace_payload *payload) +{ + int i, j, nthreads; + void *ptr; + int retval = 0; + dmnsn_raytrace_payload *payloads; + pthread_t *threads; + + /* TODO: do this portably */ + nthreads = sysconf(_SC_NPROCESSORS_ONLN); + if (nthreads < 1) { + nthreads = 1; + } + /* End non-portable section */ + + payloads = malloc(nthreads*sizeof(dmnsn_raytrace_payload)); + if (!payloads) { + return 1; + } + + threads = malloc(nthreads*sizeof(pthread_t)); + if (!threads) { + free(payloads); + return 1; + } + + /* Set up the progress object */ + dmnsn_new_progress_element(payload->progress, + nthreads*payload->scene->canvas->y); + + /* Create the threads */ + for (i = 0; i < nthreads; ++i) { + payloads[i] = *payload; + payloads[i].index = i; + payloads[i].threads = nthreads; + + if (pthread_create(&threads[i], NULL, + &dmnsn_raytrace_scene_multithread_thread, &payloads[i]) + != 0) { + for (j = 0; j < i; ++j) { + if (pthread_join(threads[i], &ptr)) { + dmnsn_error(DMNSN_SEVERITY_MEDIUM, + "Couldn't join worker thread in failed raytrace engine" + " initialization."); + } else { + free(ptr); + } + } + + free(payloads); + return 1; + } + } + + for (i = 0; i < nthreads; ++i) { + if (pthread_join(threads[i], &ptr)) { + dmnsn_error(DMNSN_SEVERITY_MEDIUM, + "Couldn't join worker thread in raytrace engine."); + } else { + if (retval == 0) { + retval = *(int *)ptr; + } + free(ptr); + } + } + + free(threads); + free(payloads); + return retval; +} + +/* Actual raytracing implementation */ +static int dmnsn_raytrace_scene_impl(dmnsn_progress *progress, + dmnsn_scene *scene, + unsigned int index, unsigned int threads); + +/* Multi-threading thread callback */ +static void * +dmnsn_raytrace_scene_multithread_thread(void *ptr) +{ + dmnsn_raytrace_payload *payload = ptr; + int *retval = malloc(sizeof(int)); + if (retval) { + *retval = dmnsn_raytrace_scene_impl(payload->progress, payload->scene, + payload->index, payload->threads); + } + return retval; +} + /* Actually raytrace a scene */ -static void -dmnsn_raytrace_scene_impl(dmnsn_progress *progress, dmnsn_scene *scene) +static int +dmnsn_raytrace_scene_impl(dmnsn_progress *progress, dmnsn_scene *scene, + unsigned int index, unsigned int threads) { unsigned int i, j, k, l; unsigned int width, height; @@ -103,14 +199,17 @@ dmnsn_raytrace_scene_impl(dmnsn_progress *progress, dmnsn_scene *scene) width = scene->canvas->x; height = scene->canvas->y; - dmnsn_new_progress_element(progress, height); - /* Iterate through each pixel */ for (j = 0; j < height; ++j) { for (i = 0; i < width; ++i) { + /* Only do the work which we were assigned */ + if ((j*width + i)%threads != index) { + continue; + } + /* Set the pixel to the background color */ color = scene->background; - t = 0.0; + t = -1.0; /* Get the ray corresponding to the (i,j)th pixel */ ray = (*scene->camera->ray_fn)(scene->camera, scene->canvas, i, j); @@ -126,13 +225,13 @@ dmnsn_raytrace_scene_impl(dmnsn_progress *progress, dmnsn_scene *scene) /* Find the closest intersection */ for (l = 0; l < dmnsn_array_size(intersections); ++l) { dmnsn_array_get(intersections, l, &t_temp); - if (t_temp < t || t == 0.0) t = t_temp; + if ((t_temp < t && t_temp >= 0.0) || t < 0.0) t = t_temp; } dmnsn_delete_array(intersections); } /* Shade according to distance from camera */ - if (t != 0.0) { + if (t >= 0.0) { sRGB.R = 1.0 - (t - 2.25)/2.25; sRGB.G = sRGB.R; sRGB.B = sRGB.R; @@ -144,4 +243,6 @@ dmnsn_raytrace_scene_impl(dmnsn_progress *progress, dmnsn_scene *scene) dmnsn_increment_progress(progress); } + + return 0; } |