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INCREASE RESOLUTION
Edit mupen64plus.cfg in .\ModLoader\emulator with these parameters;

[Video-General]
# Use fullscreen mode if True, or windowed mode if False
Fullscreen = False
# Width of output window or fullscreen width
ScreenWidth = 1600
# Height of output window or fullscreen height
ScreenHeight = "900"
# If true, activate the SDL_GL_SWAP_CONTROL attribute
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VerticalSync = False

[Video-GLideN64]
# Screen aspect ratio (0=stretch, 1=force 4:3, 2=force 16:9, 3=adjust)
AspectRatio = 3

# Enable resulted image crop by Overscan.
EnableOverscan = True
# PAL mode. Left bound of Overscan
OverscanPalLeft = 0
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# PAL mode. Right bound of Overscan
OverscanPalRight = 0
# PAL mode. Top bound of Overscan
OverscanPalTop = 0
# PAL mode. Bottom bound of Overscan
OverscanPalBottom = 0
# NTSC mode. Left bound of Overscan
OverscanNtscLeft = 4
# NTSC mode. Right bound of Overscan
OverscanNtscRight = 4
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# NTSC mode. Top bound of Overscan
OverscanNtscTop = 0
# NTSC mode. Bottom bound of Overscan
OverscanNtscBottom = 3


INSTALL TEXTURE PACK

Your texture cache file will always need to be these exact names for OoT and MM respectively:
THE LEGEND OF ZELDA_HIRESTEXTURES.htc
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ZELDA MAJORA'S MASK_HIRESTEXTURES.htc

Navigate to this directory by pasting it into your Windows explorer if you don't already know how to get there. If the cache directory does not exist, create it.
%appdata%/Mupen64Plus/cache/
Once your cache folder is created, paste your texture file in either .HTC or .HTS format with the proper naming as written above.

Edit mupen64plus.cfg in .\ModLoader\emulator with these parameters;
txHiresEnable = True
txHiresFullAlphaChannel = True

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Save and you're good.
3DS Faithful Texture Pack
https://drive.google.com/open?id=1zWBoniOcxxHGIzL_1Z-s2ZOPrRmaaff_

If using a .HTS texture file instead, you must enable these in the same .cfg file mentioned above.
txEnhancedTextureFileStorage = True
txHiresTextureFileStorage = True
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