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copied!<p>Upon further research, I think I might know the problem, but I'm not sure about this...</p> <p>From here: <a href="http://www.gamedev.net/topic/602169-opengl-drawing-cube-using-gldrawelements-and-gltexcoordpointer/page__p__4811454#entry4811454" rel="nofollow">http://www.gamedev.net/topic/602169-opengl-drawing-cube-using-gldrawelements-and-gltexcoordpointer/page_<em>p</em>_4811454#entry4811454</a></p> <blockquote> <p>This is a classical example of when you cannot use shared vertices. As soon as you introduce a vertex attribute other than position, the cube is required to have 24 vertices, not 8. The corners of a cube are not shared vertices, because they don't have the same texture coordinates.</p> <p>For example, the first two triangles are made up of the indices [0, 1, 2, 0, 2, 3], and if you reference the vertex and texture coordinate arrays, that face is fine. The second two triangles are made up of the indices [0, 4, 5, 0, 5, 1], and while the vertex array is referenced correct to make second face of the cube, the resulting texture coordinates are entirely broken.</p> </blockquote> <p>Am I right about this being my problem, or am I way off?</p> <p><strong>Edit:</strong> Almost got textures working by using more vertex positions. Now the only problem is that one face of a simple cube will be warped and diagonal to its correct position. All other faces are looking good. </p> <p>Here's the function that's almost working:</p> <pre><code>def get_json(objects, scene): """ Currently only supports one scene. Exports with -Z forward, Y up. """ object_number = -1 scene_data = [] # for every object in the scene for object in bpy.context.scene.objects: # if the object is a mesh if object.type == 'MESH': object_number += 1 # convert all the mesh's faces to triangles bpy.ops.object.mode_set(mode='OBJECT') object.select = True bpy.context.scene.objects.active = object # triangulate using new Blender 2.65 Triangulate modifier bpy.ops.object.modifier_add(type='TRIANGULATE') object.modifiers["Triangulate"].use_beauty = False bpy.ops.object.modifier_apply(apply_as="DATA", modifier="Triangulate") bpy.ops.object.mode_set(mode='OBJECT') object.select = False # add data to scene_data structure scene_data.append({ "name" : object.name, "vertices" : [], "indices" : [], "normals" : [], "tex_coords" : [] }) vertex_number = -1 # for each face in the object for face in object.data.polygons: vertices_in_face = face.vertices[:] # for each vertex in the face for vertex in vertices_in_face: vertex_number += 1 # store vertices in scene_data structure scene_data[object_number]["vertices"].append( object.data.vertices[vertex].co.x + object.location.x ) scene_data[object_number]["vertices"].append( object.data.vertices[vertex].co.z + object.location.z ) scene_data[object_number]["vertices"].append( -(object.data.vertices[vertex].co.y + object.location.y) ) # store normals in scene_data structure scene_data[object_number]["normals"].append( object.data.vertices[vertex].normal.x ) scene_data[object_number]["normals"].append( object.data.vertices[vertex].normal.z ) scene_data[object_number]["normals"].append( -(object.data.vertices[vertex].normal.y) ) # store indices in scene_data structure scene_data[object_number]["indices"].append(vertex_number) # texture coordinates # bug: for a simple cube, one face's texture is warped mesh = object.to_mesh(bpy.context.scene, True, 'PREVIEW') if len(mesh.tessface_uv_textures) > 0: for data in mesh.tessface_uv_textures.active.data: scene_data[object_number]["tex_coords"].append( data.uv1.x ) scene_data[object_number]["tex_coords"].append( data.uv1.y ) scene_data[object_number]["tex_coords"].append( data.uv2.x ) scene_data[object_number]["tex_coords"].append( data.uv2.y ) scene_data[object_number]["tex_coords"].append( data.uv3.x ) scene_data[object_number]["tex_coords"].append( data.uv3.y ) return json.dumps(scene_data, indent=4) </code></pre> <p>I'm wondering what could be the cause of only one face's texture being warped? I'm almost there, but can't seem to figure this one out.</p>

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