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iosunity-game-engineblendervuforia

If I replace teapot object of Vuforia iOS project, why only triangle seen instead of Cube?

I downloaded sample Vuforia iOS project. Instead of teapot, I want to rotate a Cube with texture. To create a cube having texture, I used blender and created a OBJ file with its UV mapping image as below:

enter image description here

In blender, it renders perfect and I can see the cube object with its texture perfectly.

Then I converted OBJ file to .h file using perl script and replaced that Teapot.h file and also replaced teapot image with PNG I attached above.

While I run the project, the cube is seen with its texture but triangles are cut for each side as below:

enter image description here

I am desperate to create custom squares, cubes having textures in existing iOS project but, I am not getting success in checking feasibility.

NOTE: My project is already developed with lots of frameworks and libraries and in one screen, I need to integrate this function.

Solution

  • I could achieve it by having add-on to Blender and then export .h file directly from Blender. There is no need to do triangulate before exporting as Unity already does the triangulation for us.

    • Download add-on from here. There is total guide on how to add it to the Blender.

    • Prepare the 3D object that you want in Blender. Check this tutorial which explains how to use Blender and make a simple 3D object having a texture around it.

    • Once you have the model that you want, go to File > Export > Vuforia OpenGL C Include as shown in below image. Save the .h file at some location

    enter image description here

    • In Vuforia iOS sample project, add this .h file and UV-mapping image (which we used to render our object) same way Teapot.h and its UV-mapping image.

    • Import the header file.

    • Replace Teapot:

    Replace

    glVertexAttribPointer(vertexHandle, 3, GL_FLOAT, GL_FALSE, 0, (const GLvoid*)teapotVertices);
glVertexAttribPointer(normalHandle, 3, GL_FLOAT, GL_FALSE, 0, (const GLvoid*)teapotNormals);
glVertexAttribPointer(textureCoordHandle, 2, GL_FLOAT, GL_FALSE, 0, (const GLvoid*)teapotTexCoords);

    with

    BlenderExportedObject object = rectObject;

glVertexAttribPointer(vertexHandle, 3, GL_FLOAT, GL_FALSE, 0, (const GLvoid*)object.vertices);
glVertexAttribPointer(normalHandle, 3, GL_FLOAT, GL_FALSE, 0, (const GLvoid*)object.normals);
glVertexAttribPointer(textureCoordHandle, 2, GL_FLOAT, GL_FALSE, 0, (const GLvoid*)object.texCoords);

    where rectObject is object name. In my case, my Blender object name was rect so it created rectObject name in .h file. Check your .h file for find that name.

    • Draw elements:

    Replace

    glDrawElements(GL_TRIANGLES, NUM_TEAPOT_OBJECT_INDEX, GL_UNSIGNED_SHORT, (const GLvoid*)teapotIndices);

    with

    glDrawElements(GL_TRIANGLES, NUM_RECT_OBJECT_INDEX, GL_UNSIGNED_SHORT, (const GLvoid*)object.indices);

    Refer to .h file to find NUM_RECT_OBJECT_INDEX.

    • That's all. It should now render any complex 3D object flawlessly.