Item model definitions using oversized_in_gui tag ignores the item model display translation override found in an item model and instead uses inventory slot order to render item models under/over each other when overlapping. This does not match previous behavior in 1.21.5 that allows item model display translation to control which models render over others in GUIs using this feature.
Steps to reproduce:
- Create an item model definition for 2 items, in this case - red_stained_glass_paneand- white_stained_glass_pane, enable- oversized_in_guitag on both definitions
assets/minecraft/items/white_stained_glass_pane
{
  "model": {
    "type": "minecraft:model",
    "model": "minecraft:item/white_stained_glass_pane"
  },
  "oversized_in_gui": true
}
assets/minecraft/items/red_stained_glass_pane
{
  "model": {
    "type": "minecraft:model",
    "model": "minecraft:item/red_stained_glass_pane"
  },
  "oversized_in_gui": true
}
- Create item models for both item definitions, give one item model a slight variation in GUI translation display and scale them up so the overlap with one another 
assets/minecraft/models/item/white_stained_glass_pane
{
  "parent": "minecraft:builtin/generated",
  "textures": {
    "layer0": "minecraft:block/white_stained_glass"
  },
  "display": {
    "gui": {
      "translation": [0, 0, -10],
      "scale": [2, 2, 2]
    }
  }
}
assets/minecraft/models/item/red_stained_glass_pane
{
  "parent": "minecraft:builtin/generated",
  "textures": {
    "layer0": "minecraft:block/red_stained_glass"
  },
  "display": {
    "gui": {
      "translation": [0, 0, 0],
      "scale": [2, 2, 2]
    }
  }
}
- Give both - white_stained_glass_paneand- red_stained_glass_paneto yourself using- /give @s minecraft:red_stained_glass_paneand- /give @s minecraft:white_stained_glass_pane
- Place - white_stained_glass_panein an inventory slot after the- red_stained_glass_pane
- Note - white_stained_glass_panerenders in front of- red_stained_glass_panealbeit item model is configured to do otherwise
Attached is the resource pack that reproduces the issue described above.
 
      
       
        
        
Thank you for your report!
After consideration, the issue is being closed as Working as Intended.
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