Add examples

examples/3d_mesh.h

@@ -0,0 +1,26 @@
+#ifndef GMIO_EXAMPLES_3D_MESH_H
+#define GMIO_EXAMPLES_3D_MESH_H
+
+#include <stddef.h>
+
+/* User-defined 3D point */
+struct my_3d_point
+{
+    double coords[3];
+};
+
+/* User-defined 3D triangle */
+struct my_3d_triangle
+{
+    struct my_3d_point vertex[3];
+};
+
+/* An example of user-defined 3D mesh */
+struct my_3d_mesh
+{
+    struct my_3d_triangle* triangle_array;
+    size_t triangle_array_count;
+    size_t triangle_array_capacity;
+};
+
+#endif /* GMIO_EXAMPLES_3D_MESH_H */

examples/occstl_read_file.cpp

@@ -0,0 +1,38 @@
+/* -----------------------------------------------------------------------------
+ *
+ * Example: read a STL file into OpenCascade StlMesh_Mesh
+ *
+ * Just give a filepath and an initialized gmio_stl_mesh_creator object to
+ * gmio_stl_read_file().
+ * The gmio_stl_mesh_creator object holds pointers to the callbacks invoked
+ * during the read operation.
+ * These callbacks creates the final mesh object.
+ *
+ * Note if you want to have control over the stream to be used, call
+ * gmio_stl_read() instead.
+ *
+ * -------------------------------------------------------------------------- */
+
+#include <gmio_core/error.h>
+#include <gmio_stl/stl_io.h>
+#include <gmio_support/stl_occ.h>
+#include <iostream>
+
+int main(int argc, char** argv)
+{
+    int error = 0;
+    if (argc > 1) {
+        // Path to the STL file
+        const char* filepath = argv[1];
+        // StlMesh_Mesh object to be constructed
+        Handle_StlMesh_Mesh mesh = new StlMesh_Mesh;
+        // Holds callbacks functions
+        gmio_stl_mesh_creator mesh_creator = gmio_stl_occmesh_creator(mesh);
+
+        // Read, using default options(NULL)
+        error = gmio_stl_read_file(filepath, &mesh_creator, NULL);
+        if (error != GMIO_ERROR_OK)
+            std::cerr << "gmio error: 0x" << std::hex << error << std::endl;
+    }
+    return error;
+}

examples/occstl_redefine_mesh_creator.cpp

@@ -0,0 +1,54 @@
+/* -----------------------------------------------------------------------------
+ *
+ * Example: redefine the callbacks of some gmio_stl_mesh_creator base object
+ *
+ * -------------------------------------------------------------------------- */
+
+#include <gmio_core/error.h>
+#include <gmio_stl/stl_io.h>
+#include <gmio_support/stl_occ.h>
+#include <iostream>
+
+// Redefine func_begin_solid of some gmio_stl_mesh_creator object
+void my_mesh_creator__begin_solid(
+        void* cookie, const gmio_stl_mesh_creator_infos* infos)
+{
+    gmio_stl_mesh_creator* base_creator =
+            reinterpret_cast<gmio_stl_mesh_creator*>(cookie);
+    base_creator->func_begin_solid(base_creator->cookie, infos);
+    // Do something more ...
+}
+
+// Redefine func_add_triangle of some gmio_stl_mesh_creator object
+void my_mesh_creator__add_triangle(
+        void* cookie, uint32_t tri_id, const gmio_stl_triangle* triangle)
+{
+    gmio_stl_mesh_creator* base_creator =
+            reinterpret_cast<gmio_stl_mesh_creator*>(cookie);
+    base_creator->func_add_triangle(base_creator->cookie, tri_id, triangle);
+    // Do something more ...
+}
+
+int main(int argc, char** argv)
+{
+    int error = 0;
+    if (argc > 1) {
+        // Path to the STL file
+        const char* filepath = argv[1];
+        // StlMesh_Mesh object to be constructed
+        Handle_StlMesh_Mesh mesh = new StlMesh_Mesh;
+        // mesh_creator to be redefined
+        gmio_stl_mesh_creator base_creator = gmio_stl_occmesh_creator(mesh);
+        // Holds callbacks functions
+        gmio_stl_mesh_creator creator = {};
+        creator.cookie = &base_creator;
+        creator.func_begin_solid = my_mesh_creator__begin_solid;
+        creator.func_add_triangle = my_mesh_creator__add_triangle;
+
+        // Read, using default options(NULL)
+        error = gmio_stl_read_file(filepath, &creator, NULL);
+        if (error != GMIO_ERROR_OK)
+            std::cerr << "gmio error: 0x" << std::hex << error << std::endl;
+    }
+    return error;
+}

examples/occstl_write_file.cpp

@@ -0,0 +1,44 @@
+/* -----------------------------------------------------------------------------
+ *
+ * Example: write a STL file
+ *
+ * Just give the filepath and an initialized gmio_stl_mesh object to
+ * gmio_stl_write_file().
+ * The gmio_stl_mesh object defines the interface to access the underlying user
+ * mesh.
+ *
+ * Note if you want to have control over the stream to be used, call
+ * gmio_stl_write() instead.
+ *
+ * -------------------------------------------------------------------------- */
+
+#include <gmio_core/error.h>
+#include <gmio_stl/stl_io.h>
+#include <gmio_support/stl_occ.h>
+#include <iostream>
+
+int main(int argc, char** argv)
+{
+    int error = 0;
+    if (argc > 1) {
+        // Path to the STL file
+        const char* filepath = argv[1];
+        // StlMesh_Mesh object to be constructed
+        Handle_StlMesh_Mesh occmesh = new StlMesh_Mesh;
+
+        // Initialize the OpenCascade StlMesh_Mesh here
+        // ...
+
+        // Will give fast access to all the triangles of the StlMesh_Mesh object
+        const gmio_stl_occmesh_iterator occmesh_it(occmesh);
+        // The gmio interface over OpenCascade's StlMesh_Mesh
+        const gmio_stl_mesh mesh = gmio_stl_occmesh(occmesh_it);
+
+        // Write binary STL little-endian, using default options(NULL)
+        error = gmio_stl_write_file(
+                    GMIO_STL_FORMAT_BINARY_LE, filepath, &mesh, NULL);
+        if (error != GMIO_ERROR_OK)
+            std::cerr << "gmio error: 0x" << std::hex << error << std::endl;
+    }
+    return error;
+}

examples/stl_read_file.c

@@ -0,0 +1,102 @@
+/* -----------------------------------------------------------------------------
+ *
+ * Example: read a STL file
+ *
+ * Just give a filepath and an initialized gmio_stl_mesh_creator object to
+ * gmio_stl_read_file().
+ * The gmio_stl_mesh_creator object holds pointers to the callbacks invoked
+ * during the read operation.
+ * These callbacks creates the final mesh object.
+ *
+ * Note if you want to have control over the stream to be used, call
+ * gmio_stl_read() instead.
+ *
+ * -------------------------------------------------------------------------- */
+
+#include <gmio_core/error.h>
+#include <gmio_stl/stl_io.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include "3d_mesh.h"
+
+/* Callback invoked at the beginning of mesh creation
+ * This is a good place to initialize your mesh object */
+static void my_3d_mesh__begin_solid(
+        void* cookie, const struct gmio_stl_mesh_creator_infos* infos)
+{
+    struct my_3d_mesh* my_mesh = (struct my_3d_mesh*)cookie;
+    size_t tri_count = 0;
+    if (infos->format == GMIO_STL_FORMAT_ASCII) /* Assume facet size ~200B */
+        tri_count = infos->stla_stream_size / 200u;
+    else /* Binary STL */
+        tri_count = infos->stlb_triangle_count;
+    my_mesh->triangle_array =
+            (struct my_3d_triangle*)malloc(
+                tri_count * sizeof(struct my_3d_triangle));
+    my_mesh->triangle_array_count = 0;
+    my_mesh->triangle_array_capacity = tri_count;
+}
+
+/* Callback invoked sequentially for each triangle in the STL mesh
+ * Just do something with the "triangle" passed in  */
+static void my_3d_mesh__copy_triangle(
+        void* cookie,
+        uint32_t triangle_id,
+        const struct gmio_stl_triangle* triangle)
+{
+    struct my_3d_mesh* my_mesh = (struct my_3d_mesh*)cookie;
+
+    if (triangle_id >= my_mesh->triangle_array_capacity) {
+        /* Capacity of the triangle array is too small, this can happen only
+         * when reading STL ascii data, where the count of triangles in not
+         * precisely known.
+         * To overcome this just grow capacity of the triangle array of 12.5% */
+        size_t new_capacity = my_mesh->triangle_array_capacity;
+        new_capacity += new_capacity >> 3;
+        my_mesh->triangle_array =
+                (struct my_3d_triangle*)realloc(
+                    my_mesh->triangle_array,
+                    new_capacity * sizeof(struct my_3d_triangle));
+        my_mesh->triangle_array_capacity = new_capacity;
+    }
+
+    { /* Copy new triangle */
+        struct my_3d_triangle* my_tri = &my_mesh->triangle_array[triangle_id];
+        const struct gmio_stl_coords* tri_vertices = &triangle->v1;
+        for (int i = 0; i < 3; ++i) {
+            my_tri->vertex[i][0] = tri_vertices[i].x;
+            my_tri->vertex[i][1] = tri_vertices[i].y;
+            my_tri->vertex[i][2] = tri_vertices[i].z;
+        }
+    }
+    my_mesh->triangle_array_count = triangle_id + 1;
+}
+
+int main(int argc, char** argv)
+{
+    int error = 0;
+    if (argc > 1) {
+        /* Path to the STL file */
+        const char* filepath = argv[1];
+        /* User-defined mesh object, to be constructed */
+        struct my_3d_mesh my_mesh = {0};
+        /* Holds callbacks functions */
+        struct gmio_stl_mesh_creator mesh_creator = {0};
+
+        /* Initialize the callback object */
+        /* -- Cookie object passed to callbacks of gmio_stl_mesh_creator */
+        mesh_creator.cookie = &my_mesh;
+        /* -- Function called initially at the beginning of a STL solid(mesh) */
+        mesh_creator.func_begin_solid = &my_stl_mesh__begin_solid;
+        /* -- Function called  for each triangle in the STL mesh */
+        mesh_creator.func_add_triangle = &my_stl_mesh__copy_triangle;
+
+        /* Read, using default options(NULL) */
+        error = gmio_stl_read_file(filepath, &mesh_creator, NULL);
+        if (error != GMIO_ERROR_OK)
+            fprintf(stderr, "gmio error: 0x%X\n", error);
+
+        free(my_mesh.triangle_array);
+    }
+    return error;
+}

examples/stl_write_file.c

@@ -0,0 +1,67 @@
+/* -----------------------------------------------------------------------------
+ *
+ * Example: write a STL file
+ *
+ * Just give the filepath and an initialized gmio_stl_mesh object to
+ * gmio_stl_write_file().
+ * The gmio_stl_mesh object defines the interface to access the underlying user
+ * mesh.
+ *
+ * Note if you want to have control over the stream to be used, call
+ * gmio_stl_write() instead.
+ *
+ * -------------------------------------------------------------------------- */
+
+#include <gmio_core/error.h>
+#include <gmio_stl/stl_io.h>
+#include <stdio.h>
+#include "3d_mesh.h"
+
+/* Callback invoked sequentially for each triangle in the STL mesh
+ * Just transfer the triangle of index 'tri_id' into 'triangle' */
+static void my_3d_mesh__get_triangle(
+        const void* cookie, uint32_t tri_id, struct gmio_stl_triangle* triangle)
+{
+    const struct my_3d_mesh* my_mesh = (const struct my_3d_mesh*)cookie;
+    const struct my_3d_triangle* my_tri = &my_mesh->triangle_array[tri_id];
+    struct gmio_stl_coords* tri_vertices = &triangle->v1;
+    for (int i = 0; i < 3; ++i) {
+        tri_vertices[i].x = my_tri[i][0];
+        tri_vertices[i].y = my_tri[i][1];
+        tri_vertices[i].z = my_tri[i][2];
+    }
+    gmio_stl_triangle_compute_normal(triangle);
+}
+
+int main(int argc, char** argv)
+{
+    int error = 0;
+    if (argc > 1) {
+        /* Path to the STL file */
+        const char* filepath = argv[1];
+        /* User-defined mesh object */
+        struct my_3d_mesh my_mesh = {0};
+        /* The interface to the user-defined mesh object */
+        struct gmio_stl_mesh mesh = {0};
+
+        /* Construct the user mesh */
+        /* ... */
+
+        /* Initialize the mesh interface */
+        /* -- Cookie object passed to callbacks of gmio_stl_mesh */
+        mesh.cookie = &my_mesh;
+        /* -- Count of triangles in the mesh */
+        mesh.triangle_count = my_mesh.facet_count;
+        /* -- Pointer on a function that retrieves a triangle from the mesh */
+        mesh.func_get_triangle = &my_3d_mesh__get_triangle;
+
+        /* Write binary STL little-endian, using default options(NULL) */
+        error = gmio_stl_write_file(
+                    GMIO_STL_FORMAT_BINARY_LE, filepath, &mesh, NULL);
+        if (error != GMIO_ERROR_OK)
+            fprintf(stderr, "gmio error: 0x%X\n", error);
+
+        free(my_mesh.triangle_array);
+    }
+    return 0;
+}