revert mesh.* with minor refactor and honey_setup_mesh()

2 files changed, 79 insertions, 75 deletions

diff --git a/src/mesh/mesh.c b/src/mesh/mesh.c
index 1889bd7..8e7e444 100644
--- a/src/mesh/mesh.c
+++ b/src/mesh/mesh.c
@@ -1,106 +1,106 @@
 #include "mesh.h"
 
+static int honey_mesh_lua_draw(lua_State* L)
+{
+    honey_mesh* mesh;
+    int shader;
+    honey_lua_parse_arguments(L, 2,
+                              HONEY_USERDATA, &mesh,
+                              HONEY_INTEGER, &shader);
+    honey_mesh_draw(*mesh, shader);
+    return 0;
+}
+
+static int honey_mesh_lua_delete(lua_State* L)
+{
+    honey_mesh* mesh;
+    honey_lua_parse_arguments(L, 1, HONEY_USERDATA, &mesh);
+    honey_mesh_delete(*mesh);
+    return 0;
+}
+
 void honey_setup_mesh(lua_State* L)
 {
     honey_lua_element mesh_elements[] = {
-        { "new", HONEY_FUNCTION, { .function = honey_mesh_new } },
-        { "draw", HONEY_FUNCTION, { .function = honey_mesh_draw } },
-        { "delete", HONEY_FUNCTION, { .function = honey_mesh_delete } },
+        { "draw", HONEY_FUNCTION, { .function = honey_mesh_lua_draw } },
+        { "delete", HONEY_FUNCTION, { .function = honey_mesh_lua_delete } },
     };
 
-    honey_lua_create_table(L, mesh_elements, 3);
+    honey_lua_create_table(L, mesh_elements, 2);
 }
 
 /* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
 
-int honey_mesh_new(lua_State* L)
-{
-    float* vertices;
-    unsigned int* indices;
-    int n_vertices, n_indices;
-    honey_lua_parse_arguments(L, 5,
-                              HONEY_USERDATA, &vertices,
-                              HONEY_USERDATA, &indices,
-                              HONEY_TABLE,
-                              HONEY_INTEGER, &n_vertices,
-                              HONEY_INTEGER, &n_indices);
-
-    size_t n_attributes = lua_objlen(L, 3);
-    unsigned int* attribute_sizes = malloc(n_attributes * sizeof(unsigned int));
-    if (attribute_sizes == NULL) {
-        lua_pushstring(L, "failed to allocate memory for vertex attributes");
-        lua_error(L);
+honey_result honey_mesh_new(honey_mesh* mesh,
+                            float* vertices,
+                            unsigned int n_vertices,
+                            unsigned int n_attributes,
+                            unsigned int* attribute_sizes,
+                            unsigned int* indices,
+                            unsigned int n_indices) {
+    if (vertices == NULL || n_vertices == 0) {
+        return HONEY_MESH_BAD_VERTEX_DATA;
+    }
+    if (indices == NULL || n_indices == 0) {
+        return HONEY_MESH_BAD_INDEX_DATA;
     }
 
     unsigned int vertex_size = 0;
     for (int i=0; i<n_attributes; i++) {
-        lua_rawgeti(L, 2, i+1);
-        attribute_sizes[i] = lua_tointeger(L, -1);
         vertex_size += attribute_sizes[i];
     }
-    lua_pop(L, n_attributes);
 
-    honey_mesh* mesh = lua_newuserdata(L, sizeof(honey_mesh));
-    mesh->n_indices = n_indices;
+    (*mesh).n_vertices = n_vertices;
+    (*mesh).n_indices  = n_indices;
 
-    glGenVertexArrays(1, &mesh->vertex_array);
-    glGenBuffers(1, &mesh->vertex_buffer);
-    glGenBuffers(1, &mesh->element_buffer);
+    glGenVertexArrays(1, &((*mesh).vertex_array));
+    glGenBuffers(1, &((*mesh).vertex_buffer));
+    glGenBuffers(1, &((*mesh).element_buffer));
 
-    glBindVertexArray(mesh->vertex_array);
+    glBindVertexArray((*mesh).vertex_array);
 
-    glBindBuffer(GL_ARRAY_BUFFER, mesh->vertex_buffer);
+    glBindBuffer(GL_ARRAY_BUFFER, (*mesh).vertex_buffer);
     glBufferData(GL_ARRAY_BUFFER,
                  vertex_size * n_vertices * sizeof(float),
                  vertices, GL_STATIC_DRAW);
 
-    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, mesh->element_buffer);
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, (*mesh).element_buffer);
     glBufferData(GL_ELEMENT_ARRAY_BUFFER,
                  n_indices * sizeof(unsigned int),
                  indices, GL_STATIC_DRAW);
 
+    /* set up vertex attributes */
     unsigned int offset = 0;
     for (int i=0; i<n_attributes; i++) {
         glEnableVertexAttribArray(i);
         glVertexAttribPointer(i,
                               attribute_sizes[i],
-                              GL_FLOAT, GL_FALSE,
-                              vertex_size * sizeof(float),
-                              (void*) (offset * sizeof(float)));
+                              GL_FLOAT,
+                              GL_FALSE,
+                              vertex_size*sizeof(float),
+                              (void*) (offset*sizeof(float)));
         offset += attribute_sizes[i];
     }
-
+  
     glBindVertexArray(0);
 
-    free(attribute_sizes);
-    
-    return 1;
+    return HONEY_OK;
 }
 
 /* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
 
-int honey_mesh_draw(lua_State* L)
-{
-    honey_mesh* mesh;
-    int shader;
-    honey_lua_parse_arguments(L, 2,
-                              HONEY_USERDATA, &mesh,
-                              HONEY_INTEGER, &shader);
-    
-    glUseProgram(shader);
+void honey_mesh_draw(honey_mesh mesh, int shader) {
+    honey_shader_use(shader);
   
-    glBindVertexArray(mesh->vertex_array);
-    glDrawElements(GL_TRIANGLES, mesh->n_indices, GL_UNSIGNED_INT, 0);
+    glBindVertexArray(mesh.vertex_array);
+    glDrawElements(GL_TRIANGLES, mesh.n_indices, GL_UNSIGNED_INT, 0);
     glBindVertexArray(0);
 }
 
 /* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
 
-int honey_mesh_delete(lua_State* L)
-{
-    honey_mesh* mesh;
-    honey_lua_parse_arguments(L, 1, HONEY_USERDATA, &mesh);
-    glDeleteVertexArrays(1, &(mesh->vertex_array));
-    glDeleteBuffers(1, &(mesh->vertex_buffer));
-    glDeleteBuffers(1, &(mesh->element_buffer));
+void honey_mesh_delete(honey_mesh mesh) {
+    glDeleteVertexArrays(1, &(mesh.vertex_array));
+    glDeleteBuffers(1, &(mesh.vertex_buffer));
+    glDeleteBuffers(1, &(mesh.element_buffer));
 }
diff --git a/src/mesh/mesh.h b/src/mesh/mesh.h
index 1f3bc3e..81bcc94 100644
--- a/src/mesh/mesh.h
+++ b/src/mesh/mesh.h
@@ -6,45 +6,49 @@
  * @brief Defines the honey_mesh struct and related basic mesh functions. 
 */
 
-
-
 #include "../common.h"
-#include "../shader/shader.h"
 
 typedef struct {
     unsigned int n_vertices, n_indices;
-    unsigned int vertex_array, vertex_buffer, element_buffer;
+  unsigned int vertex_array, vertex_buffer, element_buffer;
 } honey_mesh;
 
-/** @brief Push the mesh bindings to the lua stack. */
-void honey_setup_mesh();
+/** @brief Lua bindings for mesh drawing and deletion functions. */
+void honey_setup_mesh(lua_State* L);
 
 /** @brief Create a new mesh from vertex and index arrays.
  *
- * This function copies the data, so you can safely permit vertices and
- * indices to be garbage collected after calling it.
- *
- * @param[in] vertices Userdata array containing the vertices.
- * @param[in] indices Userdata array defining the mesh faces.
- * @param[in] attributes Lua table containing the attribute sizes.
- * @param[in] n_vertices Integer number of vertices.
- * @param[in] n_indices Integer number of indices.
+ * Note that this function creates copies of the vertex and index arrays, 
+ * so you can deallocate those immediately.
  *
- * @returns Userdata containing the mesh's OpenGL handles.
+ * @param[out] mesh Pointer to the destination honey_mesh struct
+ * @param[in] vertices Array of floats representing the vertices
+ * @param[in] n_attributes The number of attributes per vertex
+ * @param[in] attribute_sizes An array containing for each attribute how many floats it contains
+ * @param[in] n_vertices The number of vertices (NOT the number of floats in the vertex array)
+ * @param[in] indices Array of vertex indices
+ * @param[in] n_indices The number of elements in the index array
  */
-int honey_mesh_new(lua_State* L);
+honey_result honey_mesh_new(honey_mesh* mesh,
+                            float* vertices,
+                            unsigned int n_vertices,
+                            unsigned int n_attributes,
+                            unsigned int* attribute_sizes,
+                            unsigned int* indices,
+                            unsigned int n_indices);
 
 /** @brief Draw a mesh on screen.
  *
  * @param[in] mesh The mesh to draw
  * @param[in] shader The shader to use when drawing the mesh
  */
-int honey_mesh_draw(lua_State* L);
+void honey_mesh_draw(honey_mesh mesh,
+                     int shader);
 
 /** @brief Delete a mesh.
  *
  * @param[in] mesh The mesh to delete
  */
-int honey_mesh_delete(lua_State* L);
+void honey_mesh_delete(honey_mesh mesh);
   
 #endif