local function create_texture(width, height)
    -- create a new rgba texture
    local create_texture_params = {
        width  = width,
        height = height,
        type   = resource.TEXTURE_TYPE_2D,
        format = resource.TEXTURE_FORMAT_RGBA,
    }
    local my_texture_id = resource.create_texture("/my_custom_texture.texturec", create_texture_params)

    -- create a buffer with pixel data
    local buf = buffer.create(width * height, { { name=hash("rgba"), type=buffer.VALUE_TYPE_UINT8, count=4 } } )
    local stream = buffer.get_stream(buf, hash("rgba"))

    local half_width = width / 2
    for y=1, height do
        for x=1, width do
            local index = (y-1) * width * 4 + (x-1) * 4 + 1
            stream[index + 0] = x > half_width and 0xFF or 0x00
            stream[index + 1] = x > half_width and 0x00 or 0xFF
            stream[index + 2] = x > half_width and 0x00 or 0x00
            stream[index + 3] = 0xFF
        end
    end

    -- set the pixels on the texture
    local set_texture_params = { width=width, height=height, x=0, y=0, type=resource.TEXTURE_TYPE_2D, format=resource.TEXTURE_FORMAT_RGBA, num_mip_maps=1 }
    resource.set_texture(my_texture_id, set_texture_params, buf)
    
    return my_texture_id
end

local function create_atlas(texture_id, width, height)
    local params = {
        texture = texture_id,
        animations = {
            {
                id          = "my_animation_left",
                width       = width / 2,
                height      = height,
                frame_start = 1,
                frame_end   = 2,
            },
            {
                id          = "my_animation_right",
                width       = width / 2,
                height      = height,
                frame_start = 2,
                frame_end   = 3,
            }
        },
        geometries = {
            {
                width = width / 2,
                height = height,
                pivot_x = 0.5,
                pivot_y = 0.5,
                vertices  = {
                    0,         height,
                    0,         0,
                    width / 2, 0,
                    width / 2, height
                },
                uvs = {
                    0,         height,
                    0,         0,
                    width / 2, 0,
                    width / 2, height
                },
                indices = {0,1,2,0,2,3}
            },
            {
                width = width / 2,
                height = height,
                pivot_x = 0.5,
                pivot_y = 0.5,
                vertices  = {
                    0,         height,
                    0,         0,
                    width / 2, 0,
                    width / 2, height
                },
                uvs = {
                    width / 2,  height,
                    width / 2,  0,
                    width,      0,
                    width,      height
                },
                indices = {0,1,2,0,2,3}
            }
        }
    }
    local my_atlas_id = resource.create_atlas("/my_atlas.texturesetc", params)
    return my_atlas_id
end

function init(self)
    local width = 128
    local height = 128
    local my_texture_id = create_texture(width, height)
    local my_atlas_id = create_atlas(my_texture_id, width, height)

    go.set("#sprite", "image", my_atlas_id)
    sprite.play_flipbook("#sprite", "my_animation_left")

    go.set("gui#gui", "textures", my_atlas_id, { key = "my_atlas" })
    msg.post("gui#gui", "use_atlas", { texture = "my_atlas", animation = "my_animation_right" })
end

function on_message(self, message_id, message, sender)
    if message_id == hash("use_atlas") then
        local box = gui.get_node("box")
        gui.set_texture(box, message.texture)
        gui.play_flipbook(box, message.animation)
    end
end