commit 19778b950e775b996bbfa04df5a6bba2cb2d665a
parent 5dfc8fb72fbb7a1af122abf85a0b146edd02c956
Author: Egor Achkasov <eaachkasov@edu.hse.ru>
Date: Mon, 3 Mar 2025 21:31:22 +0100
Implement sionna scene loader (no material index for now)
Diffstat:
| M | scene_fromSionna.c | | | 357 | ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++------------- |
1 file changed, 298 insertions(+), 59 deletions(-)
diff --git a/scene_fromSionna.c b/scene_fromSionna.c
@@ -5,69 +5,308 @@
#include <stdio.h> /* for FILE, fopen, fclose, fseek, fgets, sscanf, printf */
#include <stdlib.h> /* for malloc */
#include <stdint.h> /* for uint8_t, uint32_t */
+#include <string.h> /* for strncmp, strrchr, strcmp */
+#include <dirent.h> /* for opendir, readdir, closedir, DT_REG */
+
+
+/**
+ * Hardcoded scenes
+ */
+
+/* Box */
+float mesh_box_vs[] = {
+ 5.f, 5.f, 0.f,
+ -5.f, 5.f, 0.f,
+ -5.f, -5.f, 0.f,
+ 5.f, -5.f, 0.f,
+ 5.f, 5.f, 5.f,
+ -5.f, 5.f, 5.f,
+ -5.f, -5.f, 5.f,
+ 5.f, -5.f, 5.f,
+};
+uint32_t mesh_box_is[] = {
+ 0, 1, 2,
+ 0, 2, 3,
+ 0, 4, 5,
+ 0, 5, 1,
+ 1, 5, 6,
+ 1, 6, 2,
+ 2, 6, 7,
+ 2, 7, 3,
+ 3, 7, 4,
+ 3, 4, 0,
+ 4, 7, 6,
+ 4, 6, 5,
+};
+HRT_Mesh mesh_box = {
+ .num_vertices = 8,
+ .vs = (float*)mesh_box_vs,
+ .num_triangles = 12,
+ .is = (uint32_t*)mesh_box_is,
+ .material_index = MATERIAL_CONCRETE,
+};
+HRT_Scene scene_box = {
+ .num_meshes = 1,
+ .meshes = &mesh_box,
+};
+const char* scene_box_filename = "box.xml";
+
+/* Simple reflector */
+float mesh_simpleReflector_vs[] = {
+ -0.5f, -0.5f, 0.f,
+ 0.5f, -0.5f, 0.f,
+ 0.5f, 0.5f, 0.f,
+ -0.5f, 0.5f, 0.f,
+};
+uint32_t mesh_simpleReflector_is[] = {
+ 0, 1, 2,
+ 0, 2, 3,
+};
+HRT_Mesh mesh_simpleReflector = {
+ .num_vertices = 4,
+ .vs = (float*)mesh_simpleReflector_vs,
+ .num_triangles = 2,
+ .is = (uint32_t*)mesh_simpleReflector_is,
+ .material_index = MATERIAL_CONCRETE,
+};
+HRT_Scene scene_simpleReflector = {
+ .num_meshes = 1,
+ .meshes = &mesh_simpleReflector,
+};
+const char* scene_simpleReflector_filename = "simple_reflector.xml";
+
+/**
+ * Read a Sionna scene
+ */
+
+/* Read a binary PLY file
+ *
+ * The PLY file have the following header:
+ * ply
+ * format binary_little_endian 1.0
+ * element vertex <num_vertices>
+ * property float x
+ * property float y
+ * property float z
+ * property float s
+ * property float t
+ * element face <num_triangles>
+ * property list uchar int vertex_index
+ * end_header
+ *
+ * \param filepath Path to the PLY file
+ * \return The mesh
+ */
+HRT_Mesh readPly(const char* filepath) {
+ FILE* f = fopen(filepath, "rb");
+ if (f == NULL) {
+ perror("Error: cannot open file");
+ exit(8);
+ }
+
+ char buf[256];
+ HRT_Mesh mesh = {
+ .num_vertices = 0,
+ .vs = NULL,
+ .num_triangles = 0,
+ .is = NULL,
+ .material_index = 0
+ };
+
+ /* read header */
+ while(fgets(buf, 256, f)) {
+ if (!strncmp(buf, "end_header", 10))
+ break;
+ if (!strncmp(buf, "element vertex ", 15)) {
+ if (sscanf(buf, "element vertex %u", &mesh.num_vertices) != 1) {
+ perror("Error: cannot read number of vertices");
+ exit(8);
+ }
+ }
+ else if (!strncmp(buf, "element face ", 13))
+ if (sscanf(buf, "element face %u", &mesh.num_triangles) != 1) {
+ perror("Error: cannot read number of triangles");
+ exit(8);
+ }
+ }
+
+ /* check if vertex and face elements are found */
+ if (mesh.num_vertices == 0 || mesh.num_triangles == 0) {
+ perror("Error: PLY element vertex or element face not found");
+ exit(8);
+ /* check if the numbers are not too big */
+ } else if (mesh.num_vertices > 1000000 || mesh.num_triangles > 1000000) {
+ perror("Error: PLY element vertex or element face too big");
+ exit(8);
+ }
+
+ /* allocate memory for vertices and faces */
+ mesh.vs = (float*)malloc(3 * mesh.num_vertices * sizeof(float));
+ mesh.is = (uint32_t*)malloc(3 * mesh.num_triangles * sizeof(uint32_t));
+
+ /* read vertices */
+ for (uint32_t i = 0; i != mesh.num_vertices * 3; i += 3) {
+ if (fread(&mesh.vs[i], sizeof(float), 3, f) != 3) {
+ perror("Error: cannot read vertex");
+ goto free_and_error;
+ }
+ /* skip s and t */
+ if (fseek(f, 8, SEEK_CUR) != 0) {
+ perror("Error: cannot skip s and t");
+ goto free_and_error;
+ }
+ }
+
+ /* read faces */
+ for (uint32_t i = 0; i != mesh.num_triangles * 3; i += 3) {
+ uint8_t n;
+ if (fread(&n, sizeof(uint8_t), 1, f) != 1) {
+ perror("Error: cannot read number of vertices in face");
+ goto free_and_error;
+ }
+ if (n != 3) {
+ perror("Error: face is not a triangle");
+ goto free_and_error;
+ }
+ if (fread(&mesh.is[i], sizeof(uint32_t), 3, f) != 3) {
+ perror("Error: cannot read face");
+ goto free_and_error;
+ }
+ }
+
+ fclose(f);
+ return mesh;
+
+free_and_error:
+ free(mesh.vs);
+ free(mesh.is);
+ fclose(f);
+ exit(8);
+}
+
+/* Read a Sionna .xml scene. Assumes meshes are in a "meshes" directory.
+ *
+ * \param filepath Path to the .xml scene file
+ * \param scene The scene to fill
+ */
+void read_scene(const char* filepath, HRT_Scene* scene) {
+ /* Check if filepath ends with ".xml" */
+ size_t filepath_len = strlen(filepath);
+ if (filepath_len > 4 && strcmp(filepath + filepath_len - 4, ".xml") != 0) {
+ perror("Error: scene file must end with .xml");
+ exit(8);
+ }
+
+ /* Get the meshes directory path */
+ const char* last_slash = strrchr(filepath, '/');
+ size_t base_len = (last_slash ? (last_slash - filepath + 1) : 0);
+ char* dir_path = (char*)malloc(base_len + strlen("meshes/") + 1);
+ if (!dir_path) {
+ perror("Error: failed to allocate dir_path");
+ exit(8);
+ }
+ if (base_len > 0) {
+ strncpy(dir_path, filepath, base_len);
+ dir_path[base_len] = '\0';
+ } else
+ dir_path[0] = '\0'; /* No directory, start empty */
+ strcat(dir_path, "meshes/");
+
+ /* Scan the directory for .ply files */
+ DIR* dir = opendir(dir_path);
+ if (!dir) {
+ perror("Failed to open meshes directory");
+ free(dir_path);
+ exit(8);
+ }
+
+ /* Count the number of .ply files */
+ uint32_t ply_count = 0;
+ struct dirent* entry;
+ while ((entry = readdir(dir))) {
+ if (entry->d_type != DT_REG) continue;
+ size_t name_len = strlen(entry->d_name);
+ if (name_len > 4 && strncmp(entry->d_name + name_len - 4, ".ply", 4) == 0)
+ ply_count++;
+ }
+
+ /* Allocate memory for the meshes array */
+ scene->num_meshes = ply_count;
+ scene->meshes = (HRT_Mesh*)malloc(ply_count * sizeof(HRT_Mesh));
+ if (!scene->meshes && ply_count > 0) {
+ perror("Error: failed to allocate meshes array");
+ free(dir_path);
+ closedir(dir);
+ exit(8);
+ }
+
+ /* Read each .ply file */
+ rewinddir(dir); // Reset directory pointer
+ uint32_t mesh_idx = 0;
+ while ((entry = readdir(dir)) && mesh_idx < ply_count) {
+ /* Continue if not a regular file or not a .ply file */
+ size_t name_len = strlen(entry->d_name);
+ if ((entry->d_type != DT_REG)
+ || (name_len <= 4 || strcmp(entry->d_name + name_len - 4, ".ply")))
+ continue;
+
+ /* Construct full filepath for the .ply file */
+ char* ply_path = (char*)malloc(strlen(dir_path) + name_len + 1);
+ if (!ply_path) {
+ perror("Error: failed to allocate ply_path");
+ free(dir_path);
+ closedir(dir);
+ free(scene->meshes);
+ exit(8);
+ }
+ strcpy(ply_path, dir_path);
+ strcat(ply_path, entry->d_name);
+
+ /* Read mesh */
+ scene->meshes[mesh_idx] = readPly(ply_path);
+ ++mesh_idx;
+
+ free(ply_path);
+ }
+
+ // Cleanup
+ closedir(dir);
+ free(dir_path);
+}
+
+
+/**
+ * Main
+ */
int main(int argc, char *argv[]) {
if (argc != 2) {
printf("Usage: %s <scene.xml>\n", argv[0]);
return 1;
}
+ const char* scene_filepath = argv[1];
+ const char* scene_filename = strrchr(scene_filepath, '/');
+ if (scene_filename == NULL)
+ exit(8);
+ else
+ ++scene_filename;
- /* TODO: parse the XML file */
- HRT_Mesh mesh_box;
- mesh_box.num_vertices = 8;
- float vs_temp[] = {
- 5.f, 5.f, 0.f,
- -5.f, 5.f, 0.f,
- -5.f, -5.f, 0.f,
- 5.f, -5.f, 0.f,
- 5.f, 5.f, 5.f,
- -5.f, 5.f, 5.f,
- -5.f, -5.f, 5.f,
- 5.f, -5.f, 5.f,
- };
- mesh_box.vs = (float*)vs_temp;
- mesh_box.num_triangles = 12;
- uint32_t is_temp[] = {
- 0, 1, 2,
- 0, 2, 3,
- 0, 4, 5,
- 0, 5, 1,
- 1, 5, 6,
- 1, 6, 2,
- 2, 6, 7,
- 2, 7, 3,
- 3, 7, 4,
- 3, 4, 0,
- 4, 7, 6,
- 4, 6, 5,
- };
- mesh_box.is = (uint32_t*)is_temp;
- mesh_box.material_index = MATERIAL_CONCRETE;
-
- HRT_Mesh mesh_simple_reflector;
- mesh_simple_reflector.num_vertices = 4;
- float vs_temp2[] = {
- -0.5f, -0.5f, 0.f,
- 0.5f, -0.5f, 0.f,
- 0.5f, 0.5f, 0.f,
- -0.5f, 0.5f, 0.f,
- };
- mesh_simple_reflector.vs = (float*)vs_temp2;
- mesh_simple_reflector.num_triangles = 2;
- uint32_t is_temp2[] = {
- 0, 1, 2,
- 0, 2, 3,
- };
- mesh_simple_reflector.is = (uint32_t*)is_temp2;
- mesh_simple_reflector.material_index = MATERIAL_CONCRETE;
+ HRT_Scene* scene_ptr;
- HRT_Scene scene;
- scene.num_meshes = 1;
- scene.meshes = &mesh_simple_reflector;
+ /* read scene */
+ /* check if the scene is a hardcoded scene */
+ if (!strcmp(scene_filename, scene_box_filename))
+ scene_ptr = &scene_box;
+ else if (!strcmp(scene_filename, scene_simpleReflector_filename))
+ scene_ptr = &scene_simpleReflector;
+ else {
+ scene_ptr = (HRT_Scene*)malloc(sizeof(HRT_Scene));
+ read_scene(scene_filepath, scene_ptr);
+ }
FILE *fp = fopen("scene.hrt", "wb");
if (fp == NULL) {
- printf("Error: cannot open file\n");
+ perror("Error: cannot open file");
return 1;
}
@@ -75,15 +314,15 @@ int main(int argc, char *argv[]) {
fwrite("HRT", 1, 3, fp);
/* SCENE */
/* num_meshes */
- fwrite(&scene.num_meshes, sizeof(uint32_t), 1, fp);
+ fwrite(&scene_ptr->num_meshes, sizeof(uint32_t), 1, fp);
/* meshes */
- for (uint32_t i = 0; i != scene.num_meshes; ++i) {
+ for (uint32_t i = 0; i != scene_ptr->num_meshes; ++i) {
/* MESH */
- fwrite(&scene.meshes[i].num_vertices, sizeof(uint32_t), 1, fp);
- fwrite(scene.meshes[i].vs, sizeof(float), 3 * scene.meshes[i].num_vertices, fp);
- fwrite(&scene.meshes[i].num_triangles, sizeof(uint32_t), 1, fp);
- fwrite(scene.meshes[i].is, sizeof(uint32_t), 3 * scene.meshes[i].num_triangles, fp);
- fwrite(&scene.meshes[i].material_index, sizeof(uint32_t), 1, fp);
+ fwrite(&scene_ptr->meshes[i].num_vertices, sizeof(uint32_t), 1, fp);
+ fwrite(scene_ptr->meshes[i].vs, sizeof(float), 3 * scene_ptr->meshes[i].num_vertices, fp);
+ fwrite(&scene_ptr->meshes[i].num_triangles, sizeof(uint32_t), 1, fp);
+ fwrite(scene_ptr->meshes[i].is, sizeof(uint32_t), 3 * scene_ptr->meshes[i].num_triangles, fp);
+ fwrite(&scene_ptr->meshes[i].material_index, sizeof(uint32_t), 1, fp);
}
fclose(fp);
