Step 2: Blitting the Characters
This is where the magic happens! While there is text to blit, this event will continue to loop, creating a new
Character object and changing it to the appropriate animation frame.
- Text of
<> ""
: Create 
at 0,0 from - : Set CurrentCharacter to Mid$(Text( "" ), CurrentPosition( "" ), 1)
- : Force animation frame to
Find(CharSheet( "" ), CurrentCharacter( "" ), 0)
- : Set ID to Find(CharSheet( "" ), CurrentCharacter( "" ), 0)
- : Set X Position to X Right( "" )
- : Add 1 to CurrentPosition
There is a lot happening here, so I will break it down and explain the purpose of each action. Remember, MMF2 executes actions sequentially and the order is very important. You can change the order of your actions from the Event List Editor (press Ctrl+L).
This simply creates a new
Character object at the co-ordinates of the
Blitter object.
- : Set CurrentCharacter to Mid$(Text( "" ), CurrentPosition( "" ), 1)
This action uses the Mid$ function to isolate the current character we are blitting. Mid$ is a function which returns a specified number of characters from within a string. Mid$ requries 3 parameters:
| Parameter |
Description |
In our case... |
|---|
| String |
The string from which characters are returned. |
Text("Blitter") |
| Start |
Specifies the starting position. |
CurrentPosition("Blitter") |
| Length |
Specifies the number of characters to return. |
1 |
So,
Mid$(string, start, length) becomes
Mid$(Text( "Blitter" ), CurrentPosition( "Blitter" ), 1)
- : Force animation frame to
Find(CharSheet( "" ), CurrentCharacter( "" ), 0)
This action uses the Find function to retrieve the numeric position of the
CurrentCharacter within the
CharSheet. The animation frame is then set to this value. Remember
CharSheet is a string containing every possible character and in the same order as the animation frames. Find is a function which retrieves the numeric position of a smaller string within a larger string. It also requires 3 parameters:
| Parameter |
Description |
In our case... |
|---|
| String |
The larger string you are searching. |
CharSheet("Blitter") |
| Query |
The smaller string you are searching for. |
CurrentCharacter("Blitter") |
| Start |
Specifies the starting position. |
0 |
So,
Find(string, query, start becomes
Find(CharSheet( "Blitter" ), CurrentCharacter( "Blitter" ), 0)
- : Set ID to Find(CharSheet( "" ), CurrentCharacter( "" ), 0)
This action stores the value returned from the Find function in each
Character object as we create it. You will see why in the next step.
- : Set X Position to X Right( "" )
This action moves the
Blitter object to the right edge of the
Character object it just created.
X Right is an MMF2 expression which returns the x co-ordinate at the right-most edge of an object.
- : Add 1 to CurrentPosition
We are using the
CurrentPosition value to keep track of which character we are blitting. So everytime we parse a character, we must add 1 to this value.
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