Journal Archive

The lead climbing is an event in which one climbs an artificial structure installed on a 15-meter-high rock wall in less than 6 minutes while wearing the safety equipments. If an athlete falls while rock climbing, they will be disqualified.

The speed climbing is a competition in which two athletes compete to climb an artificial rock wall first. Here, the height of the artificial structure is 15 meters, and the slope is 95 degrees. Also, as in lead climbing, if a climber falls while climbing, it will be disqualified.

The bouldering climbing is an event to reach the highest point in less than 4 minutes without a rope through various artificial structures installed on a 4.5-meter-high rock wall.

The combine climbing is a new event introduced at the 2020 Tokyo Olympics, and consists of a combine (or dual) event that combines the above three events [7].

Sports climbing game proposed in this paper applies the rules of speed climbing as a basic concept among the events described in Section 2, and the composition and flow of the proposed content is shown in Figure 3. The game modes consist of speed, endless, hardcore, and online competition, and the play point of view is implemented in a third person view. And, although the save function process is not expressed in the game flow in Figure 3, the automatic save function is performed upon screen change and stage completion. Endless mode is a game in which the character climbs to the highest point without making a mistake, and the difficulty increases as the character climbs higher. In addition, if a character falls in the middle of climbing, a rule to start over from the beginning is applied, and the ranking value is displayed in units of one day to induce a competitive spirit.

Fig. 3. 
Flowchart of proposed sports climbing content

Figure 4 shows the main screens of the game flow shown in Figure 3. Figure 4(a) is the character information, and Figure 4(b) is the screen for selecting the 4 game modes presented in this paper. Figure 4(c) to (f) are screens of speed and online competition mode.

Fig. 4. 
Main screens of the game flow

Figure 5 shows screens for selecting gloves, accessories, and boosters that can be found in the item shop to increase a character skill during the game. The items of gloves and accessories improve the climbing ability of character, and are designed to open the item slot according to the character level and ability.

Fig. 5. 
Main screens of the Item Shop

Gloves and accessories that can be purchased at the item shop increase the additional ability values of character that increase the health and hold distance. Acquisition of items can be purchased with coins and rechargeable gems provided in the game. And the booster serves to increase the instantaneous speed.

Table 1 shows the environment for the design and implementation of the sports climbing game proposed in this paper. 3ds Max and Photoshop were used to design objects such as backgrounds, characters, and items of the game, and Unity game engine [8] and C# script language were used to implement the flow and functions of the game.

Figures 6 to 8 show the backgrounds, characters, and gloves and accessories designed and implemented, respectively. In particular, the characters in Figure 7 are designed to be acquired according to level and experience from left to right. The characters in Figure 7 and the items in Figure 8 basically have the ability to increase the time they can hang on the rock wall and the ability to increase the hold distance. In addition, abilities such as stun duration, rockfall resistance, coin collection, and fever time are selectively or randomly granted to each character and item as shown in Table 2.

Fig. 6. 
Stage backgrounds designed and implemented

Fig. 7. 
Designed and implemented characters

Fig. 8. 
Designed and implemented items (gloves and accessories)

icon	content
	increase the strength
	decrease the stun duration
	increase the number of rockfall resistances
	increase the number of booster slots
	increase the coin collection
	increase the point collection
	increase the fever time

Users who start sports climbing games for the first time often fall during rock climbing. To overcome this, users can purchase items by raising the experience points and acquiring coins (or gems) in the training mode. Figure 9 shows the methods for obtaining coins and gems in the proposed sports climbing game. The method of acquiring coins and gems can be largely obtained through the lucky wheel, which is opened at specific time points, watching advertisements, various missions, and random boxes. Another way to obtain gems is to purchase directly through cash, but the events shown in Figure 9 have been added in order to get out of the billing-type game as much as possible.

Fig. 9. 
Events for acquiring coins and gems in the game

Figure 10 shows the playing process of the sports climbing game designed and implemented in this paper. In mobile games, most of the mission failures in the game are due to the low character level of the initial users.

Fig. 10. 
Main screens of the proposed sports climbing game

Considering these characteristics, the experience and level of character were raised through training as shown in Figure 10(a), and additional items could be acquired. And Figure 10(b) shows scenes in which rewards corresponding to experience points are obtained by performing an endless game and missions. Figure 11 shows the screens displayed when the online competition is selected in the game mode and the competition screens.

Fig. 11. 
Competition screens in online mode

This section describes major issues and functional improvements in the implementation process of the proposed sports climbing game. When a button was clicked in the process of moving a character to a nearby holder, an additional button click omission occurred due to a collision between the two functions. In addition, it was confirmed that if the animation was removed, the problem of unnatural direction such as teleportation during hold movement was confirmed.

To solve this problem, two methods were applied. In the first method, the click delay was performed by setting the animation length to within 0.2 seconds during the hold movement process. In the second method, the position weight was set by searching the position of the character's hand and holder, and a magnet effect was applied so that the character's hand was attached to the holder. And in order to prevent animation omissions, by using the animation blend provided by Unity, the character could be replaced with the corresponding motion to produce a natural animation. As a result of application, it was confirmed that even with very quick button clicks, natural animation was produced and the character moved the holder as much as the number of button clicks.