One way %Fungus decides when to start executing the Commands inside a Block is if a Block has defined an Execute On Event. If a Block has any of the possible Execute On Events chosen (such as Game Started, Message Received, Sprite Drag Completed, Key Pressed etc.) then this Block will be displayed as a **blue rounded rectangle**:
As we can see, the default Block created with every new Flowchart automatically defines the Game Started Execute On Event, so this default Block always is displayed as an Event Block.
NOTE: A Block with an Execute On Event will always appear as an Event Block in the Flowchart, regardless of whether its Commands contain menus or calls to 2 or more Blocks). In other words, in terms of Flowchart appearance, display of an Event Block overrides display of a Branching Block.
If a Block is *not* an Event Block, and its Commands include Calls and/or Menu commands to execute Commands in 2 or more other Blocks, then in the Flowchart window this Block will be displayed as a Branching Block, visually appearing as an **orange polygon**.
A whole scene's logic can rarely fit all into a single Block, therefore we need ways for one Block to pass execution control to other Blocks. There are several ways to do this, the most common being:
The Call Command tells %Fungus to go and start executing the Commands in named Block. There are several ways to do this, we can tell %Fungus to Stop execution completely in the current Block, and just pass control to named Block. We can also tell %Fungus to go and completed all Commands in the named Block, and when they are finished, to then continue executing any remaining commands in the current Block. Finally, and perhaps the most complicated/sophisticated technique, we can tell %Fungus to both started executing Commands in a named Block WHILE simultaneously continuing to execute remaining Commands in the current Block.
3. Add to Block "Start" a Say Command with the Story Text "I am in Start".
![block start]
4. Add a new Block to your Flowchart named "Block2".
5. Add to Block "Block2" a Say Command with the Story Text "I am in Block2".
![block 2]
6. Add to Block "Block2" a Call Command, by choosing menu: ```Flow | Call```:
![flow call]
7. With this Call Command Selected, in the Inspector choose Block2 from the list of Blocks for property **Target Block**:
![call block menu]
8. Note: We will keep the default of **Target Flowchart** (None), which means the current Flowchart.
9. Note: We will keep the default of **Call Mode** Stop, which means that execution in the current Block (Start) will stop once execution of the called Block has begun.
10. You should now see an arrow in the Flowchart window, connecting Block "Start" with Block "Block2". This visually tells us (the game developer) that a Call or Menu Command is present inside Block "Start" that tells %Fungus to execute commands in Block "Block2":
Let's use a Say command above to ask a tricky mathematical question, and demonstrate the Menu command by offering the user a choice been "correct' and "incorrect" answers. Menu commands transfer control to another block - so we'll need to add 2 new blocks to correspond to the 2 answers.
2. Rename the Block in the Flowchart to "Question".
3. Create a Say command, with **Story Text** to ask the question: "Is 2 + 2?".
4. Uncheck the "Wait For Click" checkbox (this is so we see the menu options immediately after the Say command has displayed the question):
![maths say command]
5. Create a new Block, named "Correct" which contains a **Say** command with the text "Well done, you are very mathematical!". Click the plus-sign button in the Flowchart window to add a new Block to the Flowchart, rename it "Correct" and then add that Say command:
![correct block]
6. Select the "Question" block, and add a Menu command by clicking the plus-sign add Command button in the Inspector and then choosing menu: ```Narrative | Menu```.
![add menu command]
7. With this new Menu command selected (green) in the top half of the Inspector window, set the **Text** to "Yes" and the **Target Block** to your new "Correct" block:
![menu command]
8. You should now see how the 'flow' of commands can change from Block "hello" to Block "Correct" in the Flowchart window:
![flow between blocks in Flowchart]
9. Add a second new Block named "Wrong", containing a Say command with text "Bad luck, perhaps consider a non-mathematical career path..."
![block for wrong answer]
10. Now we need to add another Menu command to our "hello" block, offering the user the "No" answer to our maths question, and passing control to Block "Wrong" if they disagree that 2 + 2 = 4. Select the "hello" block, and add a Menu command. With this new Menu command selected (green) in the top half of the Inspector window, set the **Text** to "No" and the **Target Block** to your new "Wrong" block.
11. You should now see in the Flowchart window how block "hello" can pass control to either block "Correct" or Block "Wrong" - depending on which menu answer the user selects.
![block connected to 2 others]
12. Run the scene, and you should see the Say question appear at the bottom of the screen, and also the two Menu buttons "Yes" and "No" in the middle of the screen. Clicking "Yes" then runs the "Correct" Block's commands, and clicking "No" runs the "Wrong" block's commands:
In the Inspector window, if you select a Call or Menu Command (executing Commands in another Block in **the same Flowchart**), then you'll see the arrow between the 2 Blocks highlighted in GREEN:
Events are one way to declare when you want execution of the Commands in a Block to begin. Typical events include:
- Game Started
- Flowchart enabled
- Message Received
- Key Pressed (Up / Down / Repeat)
- Sprite clicking / drag-dropping interactions
The most common Event used to define when a Block should start execution is, of course, the **Game Started** event. Each new Flowchart automatically starts with a single empty Block that is defined to begin execution when the game starts:
