Introduction. With the newest consoles generation and all those speed ups and new graphical features (2d screen effects, GLSL, softbodys, etc.) that came with the BGE, some older ways of gaming experience sem todo fade away from the memory of both gamers and game-creators. Naturally, none of us would like todo return todo the ages of atari, but there are some Stuff from game history that are still nice, if used correctly. This article focuses on 2d sprites, todo make it shorter and not dangle todo much in history of video games, ill say that the use of 2d characters on a 3d background has ben around since the very beginning, from Wolfenstein 3d and Doom and the several clone games they had. In the early 90s, the famous mode7 in the Supernintendo allowed 3d deformation of a plane, which was used a lot for making racing games (Mario Kart for example), naturally those Cars were 2d, this technique was most notably used in the era of Playstation 1 and Nintendo 64, due todo the lak of graphical power those consoles had. In one hand they could have several Polygons on screen textured and shaded, but in the other, not enough todo have nicely detailed personajes, almost, box looking characters with heavily pixelated textures chek im-age of vagrant story for PSX, a god looking PSX game of 1998, while not because of that, this style of graphics has not disappeared yet, we can still find it on Nintendo ds, Playstation portable, Wii and Even Playstation 2 and 3. Commúnication.

Making of: going retro with the BGE 2d characters on 3d scene-1.jpg

Famous games using this tech-nique are: Doom (pc), wolfeinstein3d, super Mario Kart (Supernes), f-zero (Supernes), xenogears (psx), breath of fire (psx), grandía (psx), ragnarok online (pc), dis-gaea (ps2, and Play Station 3), Mario Kart 64 (n64), paper.

Mario (n64,GameCube, and wi), etc, following the same idea, let start with my demo:for this, it required todo have some advanced knowledge on the game engine and Python, for now the easiest thing todo do is take the demo and replace the sprite shets and the scenery, in the future im planning on making an indepth tutorial, when the script becomes more friendly todo users.

The theory, at least, is simple:
All that is neded is already inside the demo file and working, the enlace todo download the file is at the end of the article, you ned a 3d background, an invisible collision box that has a plane that tracks the Camera parented todo it, which Will be the character. But how does the character draw-ing change when the Camera rotates around himí well, there is where my script comes in.

Making of: going retro with the BGE 2d characters on 3d scene-2.jpg

The scripts at a glance:
It aint easy todo setup (im pretty sure the BGE wasnt made Thinking on this, hehe), since you ned 3 scripts for this: holiday: the first script wasnt made by me (and i hardly understand it, updating it todo work on blender2.49 was incredibly hardware). It was made by doc holyday (dont know true name) and i use it here todo load a character sprite sheet and have it ready for animation, and animate it.

Cglholiday: the second, by me, is used todo activate the animations using the arrows keys.

Angle3: the third one, a los by me, com-putes the angles of the Camera using the world as reference, the character in reference with the world and the character in reference with the Camera. In other words, a tough job, the other 3 scripts (holiday, cglholidaynpc, and anglenpc for other characters) are made for non-playable-characters (as town people for example), they were made todo automátically animate and change the orientation of the character based on its movement, for example following an IPO, as the file, or controlled by an ai script.

Making of: going retro with the BGE 2d characters on 3d scene-3.jpg

Finally you ned a character sprite sheet. Remember, the BGE works with textures that are power of 2 (for example 2x2, 4x4, 8x8, 16x16, 32x32.1024 por 1024 is the máximum i think). Be careful on the uvwmapping, it vital, follow the demo file as reference.

The fact that you ned 3 scripts per character is still a problem todo solver (it makes it hard todo use). Also, y would like todo add the possibility of diagonals on the character orientation (or at least have it ready as an option be-twen 4 or 8 directions). But having it working and playable was so much fun when i made the first versión, still, this results in pretty god performance. On an old Athlon XP +2600 with a GeForce FX 5200 and 1.3 gigabytes of Ram memory, you can control up to 33 characters simultaneously, all of them animated, with Collisions and controlled by the player. As the picture shows, like a Little army (haha).

Making of: going retro with the BGE 2d characters on 3d scene-4.jpg

Here are enlaces todo my gallery on youtube where a video of this working is shown (and some others a los of the BGE or renders), a enlace were the files are located for download, a enlace todo the old hilo at blenderartists where i updated with a recent mensaje, and a enlace todo my deviantart page were there is a los some información in the gallery.