Scale

This page is a part of the Custom Track Tutorial. Back to the main tutorial page.

Introduction

Track scale (track size) is an important topic for Custom Track authors. A track that is scaled too small will make players hit corners on turns and complete the course too quickly. An over-scaled track will be boring and take ages to complete. Picking the right scale early is important. It takes far more time and effort to change a track's scale when the track is close to completion than it does in the early stages of the project.

Scale Factors and Percent

This article uses scale factors and percent numbers. Multiply a scale factor by 100 to get the percent value.

Examples

Factor 1.2 == 120%
Factor 0.8 == 80%

Using Meters

Making the Simple Meters template in SketchUp the default template.

Setting the Unit Scale in Blender

It is up to the creator to decide his or her preferred unit so as long as they are consistent all the way through the custom track creation process. Most modeling programs use SI (Metric) units by default. It is much easier to calculate scale changes and make measurements with SI units than English measurements (inches and feet). Therefore, it is a good practice to use meters.

It is highly recommended for SketchUp users to use the Simple Meters template. If SketchUp normally starts with a template using English measurements, set the Simple Meters template as the default template for new projects. Click on Window > Preferences then click on Template and select Simple Template - Meters from the list and press OK. 3ds Max starts up unit-less by default.

Blender uses meters by default, but they are scaled differently than the units used in Mario Kart Wii, KMP editors, and SketchUp. To fix this, open the Scene Properties menu and under Units set Unit Scale to 100. Now the values shown in Blender can match the values recommended by this article. If you do this, you will need to export the model with a scale of 0.01. Alternatively, you can use the ratio 1 Blender meter : 100 MKW Units to find equivalent values.

Choosing a Scale

Note: These recommendations are for SketchUp. Scaling factors may be different when using other 3D editors.

A good scale for the width of a road can range anywhere from 2000m to 4000m across. Narrow sections shouldn't be much less than 1500m across. Your road should be at least 3000m wide at the starting line to accommodate player starts. This all very flexible because the road width is influenced by many factors, including:

Length of straightaways
Angles of turns
Angles of slopes
The presence of off-road or guard rails
Boosts and Jumps
Boosts from nearby item boxes
Intended difficulty
"Natural" roads (dirt roads) can vary widely in width.
"Artificial" roads (streets, corridors) will have fixed widths through much of the course.

Avoid making long stretches of narrow roads without any wide sections; this can lead to problems when players fall off the track. Respawn points need to be placed on wide sections of track because when more than one player respawns at the same time, the additional players spawn to the left or the right of the respawn point. If there is no track below the player, they will be picked up by Lakitu and dropped over and over again.

It's a good idea to compare your track's scale to other custom tracks, especially if this is your first track. Many custom track models are available to download from the Google 3D Warehouse.

Inside vs Outside Drift

Mario Kart Wii vehicles have different handling characteristics. There are two main categories, vehicles that use outside drift (all karts and 9 bikes) and ones that use inside drift (Mach Bike, Flame Runner and 7 other bikes). Some turns that might be easy when using one type might be overly difficult with another. Therefore you should test your track with a variety of vehicles at different speeds to determine if your scale works for everyone.

Changing Scale

To change your track's scale, you have the following options:

Re-scale your model in your 3D editor. In SketchUp, this means using the Scale Tool. First, you should mark the zero point before scaling so you can recenter it afterwards. Then highlight the entire track and choose Scale from the Tools Menu. This is usually the best choice while you are still editing the model, and before you have finished the KMP.
You can also adjust the scale when importing your model into CTools, but it is not recommended to do this by extremely high values because it may mess up texture mapping. Adjusting the scale this way will let you use your old .obj file.
Use Wiimms SZS Tools to automatically scale the whole track. This includes the course model, vrcorn model, KCL, minimap and all KMP points. For more information see Track Transformation. This is usually the best choice when the level is complete.
Use SZS Modifier by going into the course_model MDL0, add a Matrix. Now create a new KCL using the same tool, and update your minimap, and KMP.

Scaling the entire model is not the only option. Sometimes it is better to change the width of roads or the angles of turns, especially if only certain parts of the track are problematic.

After altering your model in your 3D editor, you will also need to edit your collision model to generate an updated KCL, update your minimap and your KMP.

Recommended Scales for Retro Tracks

These recommended scales are not definitive. When possible, comparisons with Mario Kart Wii's retro tracks were made to determine the scale used by Nintendo. In other cases, the values listed here were arbitrarily made by custom track authors.

Note: Scaling factors may be different when using other 3D editors.

Mario Kart Games

Game	Scale
Super Mario Kart	Assuming that 1 pixel is 1 game unit: 40.625 for Ghost Valley 2 and Mario Circuit 3 37.5 for the walls in Mario Circuit 3
Mario Kart 64
Mario Kart: Super Circuit	Assuming that 1 pixel is 1 game unit: 31.25 for Shy Guy Beach 36 for Bowser Castle 3 27 for the walls
Mario Kart: Double Dash!!	1.2 for Peach Beach and Mario Circuit 1.44 for Waluigi Stadium and Cookie Land 1.56 for DK Mountain BCO files converted to OBJ using MKDS Course Modifier have to be additionally multiplied by 7.5.
Mario Kart DS	12 for Yoshi Falls, Desert Hills, Twilight House and GCN Mario Circuit 12.5 for SNES Mario Circuit 1 14.4 for Delfino Square, Peach Gardens and GBA Bowser Castle 2 NSBMD files converted to OBJ using MKDS Course Modifier have to be additionally multiplied by 16.
Mario Kart 7	11.1 (100/9) for Wii Mushroom Gorge, Wii Coconut Mall and Wii Maple Treeway 12.5 for Wii Koopa Cape
Mario Kart 8	For the models submitted by Ray Koopa to The Models Resource: 1000/2.54 for Wii Moo Moo Meadows 1000/2.413 for Wii Grumble Volcano
Mario Kart Tour	~ 116 for models directly ripped from Mario Kart Tour (measured in SketchUp)

Other Games

Game	Scale
Diddy Kong Racing
F-Zero (SNES)	The scale for White Land I and Big Blue was determined by measuring recharge lanes and narrow sections of track (80 pixels) and giving them a value of 2,000 game units. That works out to 25 game units per pixel. Smaller scales, such as 20 game units per pixel, would be acceptable for many tracks since the tracks vary in size.
LEGO Racers (N64)	1,600,000 (when importing the VRML into MeshLab, exporting as 3DS, and then importing into SketchUp)
Mickey's Speedway USA	The scale factor used on MSUSA Alaska and MSUSA Philadelphia are usually between 3000 and 3500 depending of the width of the track. (when importing the VRML into blender, then scaling in SketchUp)
Sonic Adventure (DX)	A scale factor of 20 was used in SADX Twinkle Circuit
Super Mario 64