Model merge for raylib

gistfile1.txt

/*******************************************************************************************
*
*   raylib [core] example - Basic window
*
*   Welcome to raylib!
*
*   To test examples, just press F6 and execute raylib_compile_execute script
*   Note that compiled executable is placed in the same folder as .c file
*
*   You can find all basic examples on C:\raylib\raylib\examples folder or
*   raylib official webpage: www.raylib.com
*
*   Enjoy using raylib. :)
*
*   This example has been created using raylib 1.0 (www.raylib.com)
*   raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
*
*   Copyright (c) 2013-2016 Ramon Santamaria (@raysan5)
*
********************************************************************************************/

#include "raylib.h"
#include "raymath.h"

Model MergeModels(Model* models, size_t count)
{
    Model outModel = { 0 };

    // count the meshes and materials in all models
    for (size_t i = 0; i < count; ++i)
    {
        outModel.meshCount += models[i].meshCount;
        outModel.materialCount += models[i].materialCount;
    }
   
    outModel.transform = MatrixIdentity();

    // allocate buffers for all combined meshes/materials
    outModel.meshes = MemAlloc(sizeof(Mesh) * outModel.meshCount);
    outModel.materials = MemAlloc(sizeof(Material) * outModel.materialCount);
    outModel.meshMaterial = MemAlloc(sizeof(int) * outModel.meshCount);

    // ingore animations
    outModel.boneCount = 0;
    outModel.bones = NULL;
    outModel.bindPose = NULL;


    // merge the meshes
    int meshOffset = 0;
    int matOffset = 0;

    for (size_t i = 0; i < count; ++i)
    {
        for (int meshIndex = 0; meshIndex < models[i].meshCount; ++meshIndex)
        {
            outModel.meshes[meshIndex + meshOffset] = models[i].meshes[meshIndex];
            outModel.meshMaterial[meshIndex + meshOffset] = models[i].meshMaterial[meshIndex] + matOffset;
        }

        for (int matIndex = 0; matIndex < models[i].materialCount; ++matIndex)
        {
            outModel.materials[matIndex + matOffset] = models[i].materials[matIndex];
        }

        // delete memory buffers used by old models
        MemFree(models[i].meshes);
        models[i].meshes = NULL;

        MemFree(models[i].materials);
        models[i].materials = NULL;

        MemFree(models[i].meshMaterial);
        models[i].meshMaterial = NULL;

        meshOffset += models[i].meshCount;
        matOffset += models[i].materialCount;
    }

    return outModel;
}

int main(void)
{
    // Initialization
    //--------------------------------------------------------------------------------------
    const int screenWidth = 800;
    const int screenHeight = 450;

    InitWindow(screenWidth, screenHeight, "raylib [core] example - basic window");

    Camera cam = { 0 };
    cam.fovy = 45;
    cam.position.z = -25;
    cam.position.y = 10;
    cam.up.y = 1;

    Model models[2];
    models[0] = LoadModel("resources/models/well.obj");
    models[0].materials[0].maps[MAP_DIFFUSE].texture = LoadTexture("resources/models/well_diffuse.png");

    models[1] = LoadModel("resources/models/cube.obj");
    models[1].materials[0].maps[MAP_DIFFUSE].texture = LoadTexture("resources/models/cube_diffuse.png");

    Model mergedModel = MergeModels(models, 2);

    SetTargetFPS(60);               // Set our game to run at 60 frames-per-second
    //--------------------------------------------------------------------------------------

    // Main game loop
    while (!WindowShouldClose())    // Detect window close button or ESC key
    {
        // Update
        //----------------------------------------------------------------------------------
        // TODO: Update your variables here
        //----------------------------------------------------------------------------------

        // Draw
        //----------------------------------------------------------------------------------
        BeginDrawing();

        ClearBackground(RAYWHITE);

        BeginMode3D(cam);

        DrawModel(mergedModel, Vector3Zero(), 1, WHITE);

        EndMode3D();
        EndDrawing();
        //----------------------------------------------------------------------------------
    }

    // De-Initialization
    //--------------------------------------------------------------------------------------
    CloseWindow();        // Close window and OpenGL context
    //--------------------------------------------------------------------------------------

    return 0;
}