I have a slot, it has a texuture, the slot appears, but not the texture.

GUI:
 

public class BWGui extends GuiContainer {

    private final int BUTTON_X = 20;
    private final int BUTTON_Y = 20;
    private static final ResourceLocation GUI_BACKGROUND = new ResourceLocation("enhancedbows", "textures/gui/workbench_gui.png");
    private static final ResourceLocation GUI_WIDGETS = new ResourceLocation("enhancedbows", "textures/gui/workbench_widgets.png");
    BWContainer container;

    public BWGui(Container inventorySlotsIn) {
        super(inventorySlotsIn);
        container = (BWContainer) inventorySlotsIn;
    }

    @Override
    public void initGui() {
        super.initGui();
        buttonList.clear();
        int id = 1;
        for(int i = 0; i < BowTypes.values().length; i++) {
            buttonList.add(new GuiButtonImage(id, BUTTON_X*((id-1)/8)+Minecraft.getMinecraft().displayWidth/10, BUTTON_Y*((id-1)%8)+Minecraft.getMinecraft().displayHeight/20, 25, 25, 64*((id-1)/8), 64*((id-1)%8), 1, GUI_WIDGETS));
            id += 1;
        }
        container.updateType();
    }

    @Override
    protected void actionPerformed(GuiButton button) {
        container.updateType();
    }

    @Override
    protected void drawGuiContainerBackgroundLayer(float partialTicks, int mouseX, int mouseY) {
        drawDefaultBackground();
        Minecraft.getMinecraft().getTextureManager().bindTexture(GUI_BACKGROUND);
        drawTexturedModalRect(this.guiLeft/3*2, this.guiTop/4, 0, 0, 256, 256);
    }

    @Override
    protected void drawGuiContainerForegroundLayer(int mouseX, int mouseY) {

    }
}

Container:

public class BWContainer extends Container {

    private TEBowWorkbench tile;
    private ItemStackHandler handler;
    public BowTypes type = null;

    BWContainer(InventoryPlayer inventory, TEBowWorkbench tile) {
        this.tile = tile;
        for(BowTypes type : BowTypes.values()) {
            if(type.ordinal() == tile.getTab()) {
                this.type = type;
            }
        }
        if(type == null) type = BowTypes.SHORTBOW;
        int i;
        for (i = 0; i < 3; ++i) {
            for (int j = 0; j < 9; ++j) {
                addSlotToContainer(new Slot(inventory, j + i * 9 + 9,
                        Minecraft.getMinecraft().displayWidth/10 + j * 18, Minecraft.getMinecraft().displayHeight/10 + i * 18));
            }
        }
        // add hotbar slots
        for (i = 0; i < 9; ++i) {
            addSlotToContainer(new Slot(inventory, i, Minecraft.getMinecraft().displayWidth/10 + i * 18,
                    Minecraft.getMinecraft().displayHeight/10));
        }
    }

    public void updateType() {
        int i = 0;
        if(type == null) type = BowTypes.SHORTBOW;
        if(handler != null)
            for(int i2 = 0; i2 < handler.getSlots(); i2++)
                inventorySlots.remove(i2);
        handler = new ItemStackHandler(type.materials.length);
    }

    @Override
    @ParametersAreNonnullByDefault
    public boolean canInteractWith(EntityPlayer playerIn) {
        return true;
    }

    @Override
    @MethodsReturnNonnullByDefault
    public ItemStack transferStackInSlot(EntityPlayer playerIn, int slotIndex) {
        ItemStack itemStack1 = null;
        Slot slot = inventorySlots.get(slotIndex);

        if (slot != null && slot.getHasStack()) {
            ItemStack itemStack2 = slot.getStack();
            itemStack1 = itemStack2.copy();
            // player inventory slots
            if (slotIndex >= 9 && slotIndex < 36) {
                if (!mergeItemStack(itemStack2, 9, 35, false))
                    return null;
                // hotbar slots
            } else if (slotIndex < 9 && !mergeItemStack(itemStack2, 2, 28, false)) {
                if (!mergeItemStack(itemStack2, 0, 8, false))
                    return null;
            } else if (!mergeItemStack(itemStack2, 0, 35, false)) {
                return null;
            }
            if (itemStack2.getCount() == 0) {
                slot.putStack(ItemStack.EMPTY);
            } else {
                slot.onSlotChanged();
            }
            if (itemStack2.getCount() == itemStack1.getCount()) {
                return null;
            }
        }
        return itemStack1;
    }
}

Misc enums are simple and I know the resource locations are correct, there are no errors in console.

I'm 99% sure I am doing a ton of things wrong with the positioning, but right now I am just focusing on getting the background textures to work.

5 hour bump.

5 hours ago, Big_Bad_E said:

I have a slot, it has a texuture, the slot appears, but not the texture. 

I'm not sure what you mean by this. Is anything drawing on your screen? Are you sure your x y positions for the drawing are correct?