Created Set Up Item Balls on a Map Without Needing New Scripts (markdown)

Set-Up-Item-Balls-on-a-Map-Without-Needing-New-Scripts.md

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+## Set Up Item Balls on a Map Without Needing New Scripts
+
+Credits to Deokishisu for implementing this feature into [CrystalDust](https://github.com/Deokishisu/CrystalDust/commit/51f995fd7821f7bd8a85272d519a34dd2604cecf).
+
+When making a hack, it's natural to want to litter various item balls containing items throughout the world. Doing this involves making a script for the item and then assigning that script to the item ball object and setting the respective flag id for when the player picks up the item.
+
+But what if we could unify the item logic for item balls so all they'd need is the one script? That's what this tutorial will help with getting set up.
+
+First, we need to go into [src/script.c](https://github.com/pret/pokeemerald/blob/master/src/script.c) and add the following function anywhere in that file:
+```c
+void GetObjectEventTrainerRangeFromTemplate(void)
+{
+    gSpecialVar_Result = gMapHeader.events->objectEvents[gSpecialVar_LastTalked - 1].trainerRange_berryTreeId;
+}
+```
+This will set the value of the object's `trainerRange_berryTreeId` (`Sight Radius/Berry Tree ID` in porymap) to `VAR_RESULT.`
+
+Next, we need to make a script making use of this function. In [data/scripts/item_balls_scripts.inc](https://github.com/pret/pokeemerald/blob/master/data/scripts/item_ball_scripts.inc), we are going to need the following script:
+```asm
+Common_EventScript_FindItem::
+	callnative GetObjectEventTrainerRangeFromTemplate
+	finditem VAR_RESULT
+	end
+```
+This will be the script all item balls will use when using this feature. Essentially, it gets the value of `VAR_RESULT` and uses it for the parameter of `finditem`.
+
+With that out of the way, we can now do this with item ball objects:
+
+![image](https://user-images.githubusercontent.com/32826900/193436571-53346610-1e82-417a-bc73-1f529e9e0353.png)
+
+So here, we have `Sight Radius/Berry Tree ID` set to `ITEM_POTION` and the `Common_EventScript_FindItem` script set to the object will set `VAR_RESULT` to `ITEN_POTION` and give that value to the `finditem` command which results in that item being obtained when the player interacts with the ball.
+
+NOTE: As long as the script set for the item ball object is set to `Common_EventScript_FindItem`, you can use the `Sight Radius/Berry Tree ID` field in porymap to get the item ID you're wanting. If the script is NOT set, it will not work.
+
+At this point however, we're done. You can either change pre-existing item balls to use this method and then give yourself a bit of extra space by removing the old item ball scripts or just have any item ball going forward use this new method, it's entirely up to you.
+
+TODO: Possibly look into using any of the Movement Radius fields in porymap to get the quantity of the respective item.