TL;DR
I've done a lot of digging into how coins work in the SM64 Decomp source and largely deduced how the interaction between Mario and coins works. I've made a behaviour that sets a hitbox to replicate this, and I can prove the hitbox works already with
So I need to make a behaviour for my mod that shifts the coin value to something other than 1, 2, or 5 when Mario collides with the object representing the behaviour. I spent like two hours digging deep into the Co-Op DX source to investigate this and have found pretty much all I could need, but clearly I'm not understanding something even deeper than everything I've already found because my Lua code simply doesn't work. Off on a tangent a bit, I first considered just trying to network the coins directly to the server counter, but not only is the method for that not exposed via Lua, but it also doesn't perform the 100-coin star check as that's done as a sibling call in all the contexts in which the network coin method is called in the Co-Op DX source.
So here's the behaviour I wrote (and yes I'm absolutely certain the behaviour is properly hooked as this isn't the first behaviour I've had to make this far into my Co-Op DX modding career):
(
From my time investigating the source, I know that interactions are processed in the
I had a few thoughts about what the issue could be but all of the thoughts have only further convinced me that this SHOULD be working.
First of all, I decided to manually test the hitbox collision myself with
This snippet, exactly as I'd expect with a fully-working coin, prints
Second of all, I tried to poll the state of
This one didn't work even when touching vanilla coins present already in the many levels of SM64, so we can probably count out this being of any reliable advice since it didn't print anything when Mario was touching my custom coin behaviour either.
Third of all, and this was my last ditch effort to understand the issue before this post, I noticed that hitboxes are scaled by the same scale as the graphical representation of an
This proved fruitless as this always just printed that the scale of the graphics for my custom
So that's it, I'm out of ideas, what am I doing wrong here? Many thanks for reading this far!
I've done a lot of digging into how coins work in the SM64 Decomp source and largely deduced how the interaction between Mario and coins works. I've made a behaviour that sets a hitbox to replicate this, and I can prove the hitbox works already with
obj_check_hitbox_overlap(), however for some reason the Object using the coin behaviour replica I made doesn't act like a coin.So I need to make a behaviour for my mod that shifts the coin value to something other than 1, 2, or 5 when Mario collides with the object representing the behaviour. I spent like two hours digging deep into the Co-Op DX source to investigate this and have found pretty much all I could need, but clearly I'm not understanding something even deeper than everything I've already found because my Lua code simply doesn't work. Off on a tangent a bit, I first considered just trying to network the coins directly to the server counter, but not only is the method for that not exposed via Lua, but it also doesn't perform the 100-coin star check as that's done as a sibling call in all the contexts in which the network coin method is called in the Co-Op DX source.
So here's the behaviour I wrote (and yes I'm absolutely certain the behaviour is properly hooked as this isn't the first behaviour I've had to make this far into my Co-Op DX modding career):
Code:
local function bhv_gonefishin_coin_init(o)
local hitbox = get_temp_object_hitbox()
hitbox.interactType = INTERACT_COIN
hitbox.downOffset = 0
hitbox.damageOrCoinValue = 1
hitbox.health = 0
hitbox.numLootCoins = 0
hitbox.radius=100
hitbox.height = 64
hitbox.hurtboxRadius = 0
hitbox.hurtboxHeight = 0
obj_set_hitbox(o,hitbox)
end(
Object deletion is not yet implemented so currently the coin just lingers in the level, but that's fine for now until I get the intended coin behaviour working in the first place)From my time investigating the source, I know that interactions are processed in the
mario_process_interactions() method of src/game/interaction.c. From that method, I know that as long as an Object spawned via spawn_sync_object() has an .oInteractType that is a bit set as part of the value for m.collidedObjInteractTypes and the hitbox of the Object is overlapping the hitbox of m.marioObj, then a collision and more importantly an interaction should occur. In the snippet above, the ObjectHitbox I define is one-for-one the yellow coin hitbox from the SM64 decomp source code included within Co-Op DX's source. Additionally, I know from further source poking that obj_set_hitbox() is just a method to transfer the data of an ObjectHitbox to various members of the Object type such as hitbox.interactType to Object.oInteractType. Yet, despite all this, the Object(s) that this behaviour is attached to do not act like coins when Mario touches them.I had a few thoughts about what the issue could be but all of the thoughts have only further convinced me that this SHOULD be working.
First of all, I decided to manually test the hitbox collision myself with
obj_check_hitbox_overlap() as seen in the snippet below
Code:
id_bhvGoneFishinCoin = hook_behavior(nil,OBJ_LIST_DEFAULT,true,function(o) bhv_generic_init(o) bhv_gonefishin_coin_init(o) end,function(o)
local hittingMario = obj_check_hitbox_overlap(o,gMarioStates[0].marioObj)
log_to_console("mario hit: "..tostring(hittingMario))
end,"bhvGoneFishinCoin")This snippet, exactly as I'd expect with a fully-working coin, prints
mario hit: true whenever Mario has his hitbox overlapping with that of the coin Object and mario hti: false at all other times.Second of all, I tried to poll the state of
m.collidedObjInteractTypes every frame making sure that the INTERACT_COIN bit was set and printing a message if so to the console, like so:
Code:
hook_event(HOOK_MARIO_UPDATE,function(m)
if(m.playerIndex==0) then
if(m.collidedObjInteractTypes & INTERACT_COIN ~=0) then
log_to_console(string.format("touching a coin | %.1f",get_global_timer()))
end
end
end)This one didn't work even when touching vanilla coins present already in the many levels of SM64, so we can probably count out this being of any reliable advice since it didn't print anything when Mario was touching my custom coin behaviour either.
Third of all, and this was my last ditch effort to understand the issue before this post, I noticed that hitboxes are scaled by the same scale as the graphical representation of an
Object in-game. Assuming that maybe somehow the graphical scale was off-kilter by default, I decided to print the scale channel values like so:
Code:
djui_chat_message_create(string.format("gfx scale: %.1f,%.1f,%.1f",o.header.gfx.scale.x,o.header.gfx.scale.y,o.header.gfx.scale.z))This proved fruitless as this always just printed that the scale of the graphics for my custom
Object were, as-expected, (1,1,1), meaning the scale of the graphics ultimately had no effect on the hitbox dimensions.So that's it, I'm out of ideas, what am I doing wrong here? Many thanks for reading this far!
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