Game Development Reference
In-Depth Information
Note
The
OnGUI
function acts in a similar way to an
Update
function, but
OnGUI
gets called
more than once for rendering and handling the
GUI
events, meaning that the
OnGUI
im-
plementation might be called several times per frame (one call per event), which means it
is recalculated at least twice per frame, which can make it slow than another
GUIEle-
ment
(
GUITexture
or
GUIText
). More importantly, each
GUI
object will also create
one or more draw calls, which means that this can cause a performance hit easily. So, it's
not recommended to use
OnGUI
for the in-game UI (especially in game development), in-
stead, we can use
GUIElement
.
Draw calls is how many materials from each object are being drawn to the screen. Around
200 to 300 draw calls is considered acceptable on a mobile platform.
Also, there are many remarkable UI tools in the assets store that are easier to implement
and they have a great performance for mobile development, such as the new GUI system
(uGUI) on Unity 4.6, NGUI (recommended), and EZGUI.
On the other hand, the
GUI
class can also be used with the
editor
class to create a cus-
tom inspector or window in Unity, which is very helpful. (We will learn about this in a
later project.)
In this project, we will apply the custom GUI graphics to Unity by using
GUISkin
. We
can have multiple styles for our GUI graphics in Unity. Let's say that we have multiple
types of fonts that we want to use in our menu; Unity has a way to do this. We can create a
GUISkin
element and apply our custom skin to the area that we want to show the font in.
That is the great thing about Unity.
First, we will create the
Item
,
ItemsContainer
, and
SkillsContainer
classes to
contain our items and equipments. Then, we will create a menu scripting class that will
bring up a new menu window in the game scene when the player presses the
M
key. Next,
we will generate a script to create three tab buttons, which will take the player to each
window,
STATUS
,
INVENTORY
, and
EQUIPMENT
.
In the
STATUS
tab, we will create a script that will show the image of our character, hit
points, magic points, skills, and all attributes of this character. Next, we will create the
INVENTORY
tab, which will contain all the items that the player can scroll up and down
to choose an item. Finally, we will create the
EQUIPMENT
tab that the player can use to
manage and change the equipments and skills of the character by clicking on it.
