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Member Since 01 Mar 2011
Offline Last Active Dec 08 2012 09:50 AM

Topics I've Started

Android development with Xcode and other libraries (C++)

12 July 2012 - 12:37 PM

I've found several mini-tutorials with setting up Android projects in Xcode and that it is possible to use C++ language too.

However, I have other libraries I'd like to use that are, as I've read, Android compatible.

I'm just not sure how to set this up. The libraries are all cross-platform. OpenGL for graphics and OpenAL for audio.

Let me know if I need to tell you anything else to help me out.


Need help with pseudo lights and shadows in 2d tiled-based game

28 June 2012 - 11:50 AM

I have an implemented algorithm to generate these shadows and lights and it does fine. My problem is with the speed.
Observe some screenshots:

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Several Multi-colored Lights with NO Shadows. Get a solid 60 fps....

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Lights WITH shadows. Generates 20-30~ fps. Speed reduces even further after 5 or so more lights in the map...

The Concept.

1. Pre-Lighting. It the checks to see if any light_groups have been added to the map and iterates through each visible tile on screen and applies each light to it. If the tile is off-screen or pitch black, it simply isn't drawn.

2. Light Calculation. Each light casts line checks to see if the tile is blocked by a wall tile (to reduce the light value the final tile may receive.) If so, the light value is cut immensely and is returned. If not, full light value is returned.

3. Light Baking. The final color value from the lights are applied to the tile (keeping a threshold between 0-255).

This process is repeated for each tile on-screen until all tiles are affected by the light sources.

The Problem.

Each tile through each light is costly. The screen is 600x400, so there are about 950 tiles to iterate through. Currently 5 light sources.

That's a lot of calculation that I'm sure could be reduced.

The Code.

Light Group and calculation.
#include "MapLightGroup.h"
MapLightGroup::MapLightGroup(GenericTiledMap *generic_tiled_map)
	map = generic_tiled_map;
const Light::Color MapLightGroup::calculateLight(const Vector2D point)
	Light::Color final_color, current_color;
	final_color.r = 0;
	final_color.g = 0;
	final_color.b = 0;
	final_color.a = 1;
	// Map cell dimensions
	int cell_w = map->getCellWidth();
	int cell_h = map->getCellHeight();
	for(int i = 0; i < getSize(); i++)
		bool blocked = false;
		if(get(i)->getPosition().distance(point) < get(i)->getCutoffDistance())
			if(map->lineIntersection(get(i)->getPosition().x/cell_w, get(i)->getPosition().y/cell_h,
									 point.x/cell_w, point.y/cell_h,
									 0, 0, 0))
				blocked = true;
		// If the light source is beyond a block, darken it.
			current_color = get(i)->calculateLight(point);
			final_color.r += current_color.r/10.0;
			final_color.g += current_color.r/10.0;
			final_color.b += current_color.r/10.0;
			final_color.a += current_color.r/10.0;
			//final_color.r = 0;
			//final_color.g = 0;
			//final_color.b = 0;
			current_color = get(i)->calculateLight(point);
			final_color.r += current_color.r;
			final_color.g += current_color.g;
			final_color.b += current_color.b;
			final_color.a += current_color.a;
	// limit threshold to 0-255
	return final_color;

The individual light calculation code:
const Light::Color Light::calculateLight(Vector2D point)
    Light::Color final_color;
    double dist = light_position.distance(point);
    if(dist <= 1) dist = 1.0;
    if(dist >= light_cutoff)
	    final_color.r = 0;
	    final_color.g = 0;
	    final_color.b = 0;
	    final_color.a = 1;
	    return final_color;
    double dist_light_factor = dist*light_tightness;
    double light_scalar = 1.0/(dist_light_factor/(light_radius*light_spread_weight));
    final_color.r = light_color.r * light_scalar;
    final_color.g = light_color.g * light_scalar;
    final_color.b = light_color.b * light_scalar;
    final_color.a = light_color.a * light_scalar;
    return final_color;

The map drawing code.

void ZombieGameTiledMap::draw(Camera *cam, LightGroup *lights)
	if(cam == 0)
	int cell_width  = getCellWidth();
	int cell_height = getCellHeight();
	for(int k = 0; k < getNumLayers(); k++)
		for(int i = 0; i < getMapWidth(); i++)
			for(int j = 0; j < getMapHeight(); j++)
				GenericTiledMap::Tile tile = getTile(i, j, k);
				if(tile.getCellID() - 1  < 0)
				if(!cam->isPositionInView(Vector2D(i*cell_width, j*cell_height)))
				Gosu::Color c = Gosu::Colors::white;
				c.setAlpha( map_parser->getLayer(k).opacity * 255 );
				Vector2D coord = cam->worldToScreen( Vector2D( (i*cell_width), (j*cell_height) ) );
				if(lights != 0)
					Light::Color color;
					Vector2D point = Vector2D(i*cell_width, j*cell_height);
					color = lights->calculateLight(point);
					if(color.r == 0 && color.g == 0 && color.b == 0)
					// RED
					double red = color.r;
					if(red > 255) red = 255;
					c.setRed( red );
					// GREEN
					double green = color.g;
					if(green > 255) green = 255;
					c.setGreen( green );
					// BLUE
					double blue = color.b;
					if(blue > 255) blue = 255;
					c.setBlue( blue );
				double scale = cam->getZoom();
				// NOW DRAW
				v_img[tile.getCellID()-1].draw(coord.x, coord.y, k, scale, scale, c);

The Help.

If there is any more information needed (i.e. more code), please let me know. I want to be able to have decent results with better speed.

Also, another achievement I'd like is less blocky shadows if possible. If some kind of smoother interpolation between shadow'd tiles is possible, inform me.

Thank you.

iOS app development. Newer iPad or does it really matter?

19 June 2012 - 11:24 AM

I have been writing games lately that I ultimately want to see as an app for the iPad and other iOS touch devices. I have everything but an iOS to test the porting on.

I was going to buy a refurbished iPad1 for testing purposes only as I figured I didn't need a brand new one just to see if something runs right.

However, are there aspects I'm not thinking about that will really determine what I need to buy? (iPad, iPad2, or the newer one?)

Any feedback would be greatly appreciated.

Free "RPG esque" Background Music

15 June 2012 - 12:10 PM

Made some music a while back for an "action anime RPG game" but the director of the game wanted music more arcade-like (with metal guitars strumming in the background and cheesy synths). I straight-up told him that I felt it would not be a good direction for the game (as it was a really impressive one) and I wouldn't make such music knowing the music he wanted wouldn't fit. I couldn't have that on my consciousness. He politely informed me that there were others that would make his music. So that was that.

So anyways, I have music free to use and currently only a few:
  • 3 alternative title screen pieces
  • 2 alternative "gear"/mech dungeon level pieces
  • 1 catacombs piece
Download the current Archive.

Just slap my name somewhere and include the copyright .html files in your game. I do plan on expanding this library to be a full-fledge free-to-use background-music-for-games library, so when I make more pieces, I'll either update here or make a new post.


Any video formats that are free to use?

31 May 2012 - 11:19 AM

"Use" as in with your application and free to parse without needing to buy a license. Also, preferably have audio as well.

I did find Theora. Has anyone used this before? If so, what was your experience with it?