LinsenBlog

Suddenly a sky-renderer! How awesome it!? Believe it or not, this didn't take long to implement due to the awesome amount of code and explanations provided in this web article on atmospheric sky rendering. The hardest part was actually figuring out how the rest of my team did rendering so that my render pass didn't mess anything up.

I chose a poor time to write this blog update as I don't have the time to commit to actually writing a step-by-step tutorial outlining how I did this, but maybe I'll come back and update it.

Here's the basics:

1. Disable OpenGL's depth testing with glDisable(GL_DEPTH_TEST);
2. Prepare a textured quad (a.k.a. a square) to be rendered as the first thing after you call glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
3. Render that quad using the sky shaders you build from the above tutorial.
4. Re-enable depth testing so the rest of your scene doesn't go kaput: glEnable(GL_DEPTH_TEST);

Easy right? (It will honestly take some work, but as you can see it's oh-so-worth it).

Cheers until next time!

WOOP. Here's the first of many devblogs for my CPE 476 project! And by many I mean probably like 3.

The game

I should probably mention some details about the game before I go rambling off about what I've put into it so far. RBGZero is a hybrid of a few game types. The controls and 'track' come from Audiosurf, the feel and speed of the game from the F-Zero series, and a small rhythm game basis inspired by Audiosurf, Thumper, and the BIT.TRIP series. We're hoping to combine these together to create a pseudo-on-rails racer that pits you against your reflexes and your ability to predict rhythm patterns in music. The goal: travel as far as you can before the song/track ends while avoiding and also destroying obstacles. RGB comes from the fact that there are 3 colored lanes that give your ship 3 different colored shields as you race. Hitting a similar colored obstacle will destroy it and give you a speed boost. Obstacles are timed with the background music, so feeling the rhythm of the song is key for traveling far distances. That's about it.

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Shadows

So each member of my team was assigned a 'major technology' to implement in our game. I unwisely chose shadow maps. I say this not because understanding how to do shadow maps was incredibly hard (though it took a few readings), but because our codebase was not initialized to handle multiple render passes with different shaders and steps very well. Thus, IMPLEMENTATION was what made this super hard. I basically followed the tutorial here and un-saddened as much of the codebase as I could to get the result you see at the top of this post. There is still a good amount of shadow acne when the camera is moved around and some peter-panning is also present, but I think they look pretty good! Now that that's taken care of, it's time to make a BeatMap reader and object spawner!

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Overview

Beat Block Barrage (BBB) is a 2-player game where one player attempts to avoid an onslaught of multi-speed beat boxes launched by the opposing player. The Block player controls with the ASW keys and the Ship player controls with the JK keys.

Disclaimer/F.Y.I.

BBB was actually meant to be a rhythm-based endless runner. However, getting an Audio library working took the backseat once other problems/features emerged. Thus, while playing around with the block spawner I thought it would be fun to leave BBB as a multiplayer game that could eventually support rhythmic timing.

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Techy Details

• Views and Camera Angle

Toying with the eye point and lookat point of the camera actually took up a good amount of my intial time working on this project. I wanted a slightly restricted view so the player wasn't presented with too bland of a scene, but I also needed to have enough space for the player to both see the block spawner and have time to prepare for faster moving blocks.
I ended up with a high camera placed above the ground looking down towards the middle of the 'track'.

• Smooth Movements

The smoothness seen when the ship moves left and right is simply done using an exponential equation. As the user moves left or right, a destination is set in the corresponding lane. The ship then rotates and moves towards the lane, covering 1/4 the remaining distance each frame. When the ship gets within 0.1 world units of its destination, the destination is 'set' as the ship's current position. The camera moves the same way, but is scaled slightly less.

• Cube System

The Cube management system was the hardest part of the project (aside from spending 5hrs on OpenAL just to get nothing working).
Cubes are kept track of via a std::vector with a max_size that is set in the globals. When a player spawns a cube, it is added to the vector and is given an interval (at which to move). A timer is kept during the game's runtime and that timer ticks every 1/4 second (a 16th note in a 120BPM song). When a tick happens, all non-moving blocks have an interval taken away. When that interval between moves reaches 0, the cube begins animation. When it finishes the animation after interval*4 many frames, the cube is checked for being offscreen, collision with ship, and if it needs to restart its interval animation timer. Cubes that have left the screen are erased from the vector.

• UI

Since an actual UI was out of the scope of my skills, I decided to represent important player details with well placed models that help teach players what's going on as the game progresses. The UI is just 12 models placed on either side of the track.

• "Particle" Effects

What kind of graphics project would this be if a Stanford bunny wasn't featured? The thrusters on the back of the ship release wavering clouds of bunnies as the ship 'moves forward'. The bunnies are all managed with another vector and have an initial position, final position, and velocity. Each frame, the bunny is progressed towards its destination on a scale with its velocity. Its X position is then slightly randomized so that the bunnies kind of vibrate back and forth. This combined with their rotation gives a suuuper slight image of smoke if you look at it right!

• Music

Because this was (and still is) planned to be a rhythm game, I put together an Electronic track to be played along with game while its running. The blocks sync together with the music pretty well for the most part, the so rhythm aspect of the project was not completely thrown out.

• External Libraries / Credits

I used none, though I did get some Rubber Ducky help from my friend Aaron Jacobs. However, we were unable to meet to get FMOD working, which is why I ended up abandoning it so abruptly.

I've finally gotten around to doing an assignment for my 3D modeling class that I'm ok with showing off. The last week in class we've been learning how to assign materials and colors to created objects, so it was only fair to ask us to do those tasks when creating a lava lamp in Maya. For someone who is in no way a graphic artist, I have to say that this render of my lamp looks pretty nifty. You got sweet shadows, smooth reflections, ambient and spot lighting, and neon orange goop to tie it all together.

In just a little few weeks, I should have a short film animated by myself and a classmate to post, so be on the lookout! Yay 3D modeling! If you have a copy of Maya and would like to attempt to create a lamp as well, visit this tutorial.

Someone reading this post may or may not recognize the above bunny. It's a pretty iconic little figure in the computer graphics world. Anyway, the above bunny is one that I generated, displayed and colored! Ain't that a hoot? Given a whole bunch of ASCII, I created a pretty looking, nicely shaded bunny. This process is called rasterization. It's a time consuming and process consuming endeavor, but it's one of the final steps in the graphics pipeline - that is, going from a set of 'world coordinates' to a fully displaying image.

This was done for a Computer Graphics class I'm currently taking. The best part about this class is that I was allowed to take an upper division Art class without the prerequisites. So in addition to turning .obj files into actual interactive media, I get to learn how to create those initial .obj files as well using Maya. I'll be updating this blog with creations from both those classes and my iOS Development class, so stay tuned!