Summary of ¿Cómo funciona WOLFESTEIN 3D? 🔫 Su motor EXPLICADO. Así se trazaban rayos en 1992.

00:00:00 - 00:25:00

In the YouTube video "¿Cómo funciona WOLFESTEIN 3D? 🔫 Su motor EXPLICADO. Así se trazaban rayos en 1992," Mind the game explores the workings of Wolfenstein 3D, a groundbreaking 1992 PC game developed using the raycasting technique. John Carmack, the game's programmer, invented a new graphic mode, "13y," to enable improved double buffering and 256 colors in Wolfenstein 3D. The game featured both 2D and 3D areas, where 3D sections occupied a selectable portion of the screen up to 304x152 pixels. The speaker explains how Wolfenstein 3D created the illusion of depth by casting lines from the player's perspective and determining which walls the lines hit based on a 2D map of the level. Textures for walls were then scaled according to the length of the lines, creating the illusion of perspective and depth. Wolfenstein 3D used a simpler form of ray tracing called raycasting, which involved shooting a single ray and stopping at the first collision point. Despite relying on raycasting and only requiring 304 rays per frame, the speaker notes the differences between ray calculations and complexity between raycasting and current 3D ray tracing techniques. He also discusses how objects, including enemies and decorations, were represented as 2D sprites in a 3D world, allowing for the illusion of depth through scaling and painting techniques. While Wolfenstein 3D had limitations, such as being unable to look up or down, it paved the way for innovation in the gaming industry.

• 00:00:00 In this section of the video titled " ¿Cómo funciona WOLFESTEIN 3D? 🔫 Su motor EXPLICADO. Así se trazaban rayos en 1992," Mind the game explains how Wolfenstein 3D, a PC game developed in 1992, functioned through a technique called raycasting, which differed from raytracing. Working with a VGA graphic card, John Carmack, the game's programmer, invented a new graphic mode called "13y" to enable 256 colors, disable memory control, and maintain non-square pixels, allowing for improved double buffering and resulting in smoother gameplay. The game featured both 2D and 3D areas, where the 3D part occupied a selectable portion of the screen, up to 304x152 pixels, and the user could choose the resolution depending on their machine's performance. Wolfenstein levels were created using maps with 64x64 squares, representing 8-feet sides, and were composed of walls and doors, which occupied complete squares.
• 00:05:00 In this section of the YouTube video titled "¿Cómo funciona WOLFESTEIN 3D? 🔫 Su motor EXPLICADO. Así se trazaban rayos en 1992," the speaker explains how the Wolfenstein 3D game engine creates the illusion of depth in its 2D environments to make them appear 3D. This is accomplished by casting lines from the player's perspective and determining which walls those lines hit based on a 2D map of the level. Textures for the walls are then scaled according to the length of the lines, with longer lines corresponding to farther walls, giving the illusion of perspective and depth. The speaker also clarifies that Wolfenstein 3D uses ray casting, which is a simpler form of ray tracing, involving shooting a single ray and stopping at the first collision point, not the recursive ray tracing commonly associated with modern ray tracing techniques.
• 00:10:00 In this section of the video, the speaker explains how the rays are traced in Wolfenstein 3D, a classic first-person shooter game from 1992. While current games trace rays in 3D and require millions of rays per frame for complex scenes, Wolfenstein 3D uses ray-casting and traces rays in a 2D grid, requiring only 304 rays per frame. The speaker discusses the differences in ray calculations and complexity between the two approaches and notes that ray-tracing has been used in video games for other purposes such as physics and sound propagation despite being less common in graphics. While Wolfenstein 3D used a simple method to trace rays square by square on the map grid, more advanced techniques have since been developed to trace rays in 3D.
• 00:15:00 In this section of the video titled "¿Cómo funciona WOLFESTEIN 3D? 🔫 Su motor EXPLICADO. Así se trazaban rayos en 1992", the speaker discusses how the objects in Wolfenstein 3D, including enemies and decorations, are represented as 2D sprites in a 3D world. These sprites are always drawn facing the camera and are used for both static objects and animated enemies. The process of painting these sprites on the screen involves checking which visible squares on the walls contain sprites, calculating their height based on their distance from the camera, and scaling and painting them accordingly. Despite the game's use of sprites, it also has limitations, such as being unable to look up or down due to the way walls and sprites are painted, and having no lighting or shadows.
• 00:20:00 In this section of the video, the speaker explains the process of ray tracing and painting walls in Wolfenstein 3D. The game used a geometric operation called the square root to calculate the length of rays and create an illusion of depth. However, this was computationally expensive for 1992 PCs. Instead, they calculated the minimum distance to the camera plane and used trigonometric operations, specifically sines and cosines. Unfortunately, calculating these functions was also expensive, so they pre-calculated values and stored them in tables to avoid constant calculations during the game. The game also made use of column scaling, which allows output heights to be even numbers between 2 and 512 pixels. The game's impressive performance on older processors was due to Carmack's decision to program 256 scaling functions, each optimized for a single size. However, this took up too much memory, so they approximated scales every 4 pixels, resulting in noticeable jumps. Another improvement was deferred column drawing, which groups columns with similar vertical sizes to reduce the number of rescale operations, although it results in steps on walls or objects.
• 00:25:00 In this section of the YouTube video titled "¿Cómo funciona WOLFESTEIN 3D?", the speaker discusses the advanced optimization and innovation of Wolfestein 3D, a pioneering first-person shooter game developed by Id Software in 1992. He emphasizes that its code was capable of writing multiple columns at the same time, saving valuable time. The speaker then shares his resources for researching Wolfestein 3D, including the books "Masters of Doom" by David Kushner and "Game Engine Black Book: Wolfenstein 3D" by Fabien Sanglard. He details how these sources helped him understand the engine's inner workings, allowing him to modify the game's behavior. The speaker also shares his gratitude to RoxSP, who recommended the books and provided insights into compiling Wolfestein 3D on a current machine. Lastly, the speaker expresses his admiration for Id Software's rapid technological advancement, which paved the way for the even more groundbreaking game, Doom, released the following year.