Author Topic: [Ndless] Tunnel (Read 27756 times)

Spenceboy98 · « **on:** June 17, 2013, 04:08:44 pm »

Hello all. I saw this tutorial on how to make a tunnel and I decided to port it to Nspire. I'm having problems though. It only displays half of the tunnel correctly(the right side).

Could you guys help(I directly ported the code from the tutorial)?

Gif is attached(faster on calc).

lkj · « **Reply #1 on:** June 17, 2013, 05:24:58 pm »

Well, most likely you made a mistake while porting, so we'd need to look at your code to help?

DJ Omnimaga · « **Reply #2 on:** June 17, 2013, 05:26:48 pm »

You might have to post the code so C users can help you easier. By the way this looks kinda nice so far. How will obstacles be drawn? Also are the vertical lines due to some compression to save speed? Not that it looks bad, but just curious.

Spenceboy98 · « **Reply #3 on:** June 17, 2013, 06:05:05 pm »

I don't know why the lines are there.

Here is my code:

Spoiler For Code:

Code: [Select]

#include <os.h>
#include "utils.c"
#include "graphics3.c"
#include "touchpad.c"

#define texWidth 256
#define texHeight 256
#define screenWidth 240
#define screenHeight 240

int w = 240, h = 240, x, y;

int texture[texWidth][texHeight];

int distanceTable[screenWidth][screenHeight];
int angleTable[screenWidth][screenHeight];
int buffer[screenWidth][screenHeight];

void masksprite(void *buffer, int *data, int x, int y, int width, int height, int mask){
	int i, j;
	for(i = 0; i < height; i++){
		for(j = 0; j < width; j++){
			if(data[i*width+j] != mask && x+j < 320 && x+j > 0 && y+i < 240 && y+i > 0){
				setPixelBuf(buffer, x+j, y+i, data[i*width+j]);
			}
		}			
	}
}

uint16_t RGBColor(uint8_t r, uint8_t g, uint8_t b)
{
  return ((r / 8) << 11) | ((g / 4) << 5) | (b / 8);
}

int main(void) {
	char *screen;
	screen = (char*)malloc(SCREEN_BYTES_SIZE * sizeof(char));     // just a buffer 
	if(!screen) 
	{ 
		exit(0); 
	} 
	initTP();
	lcd_ingray();
	for(x = 0; x < texWidth; x++)
    for(y = 0; y < texHeight; y++)
    {
		uint8_t c = x ^ y;
        texture[x][y] = RGBColor(c, c, c);
    }
	for(x = 0; x < w; x++)
    for(y = 0; y < h; y++)
    {
        int angle, distance;
        float ratio = 32.0;
        distance = (int)(ratio * texHeight / sqrt((x - w / 2.0) * (x - w / 2.0) + (y - h / 2.0) * (y - h / 2.0))) % texHeight;
        angle = (unsigned int)(0.5 * texWidth * atan2(y - h / 2.0, x - w / 2.0) / M_PI);
        distanceTable[x][y] = distance;
        angleTable[x][y] = angle;
    }
	float animation = 0;
	int shiftY = (int)(texHeight * 0.25);
    //begin the loop
    while(!isKeyPressed(KEY_NSPIRE_ESC))
    {
        animation = animation+0.01;
		readTP();
		int TZ = getTouchedZone4();
        //calculate the shift values out of the animation value
        int shiftX = (int)(texWidth * 1.0 * animation);
		if(isKeyPressed(KEY_NSPIRE_RIGHT) || TZ==6)
			shiftY++;
		if(isKeyPressed(KEY_NSPIRE_LEFT) || TZ==4)
			shiftY--;
        for(x = 0; x < w; x++)
        for(y = 0; y < h; y++)
        {
            //get the texel from the texture by using the tables, shifted with the animation values
            int color = texture[(unsigned int)(distanceTable[x][y] + shiftX)  % texWidth][(unsigned int)(angleTable[x][y] + shiftY) % texHeight];
            buffer[x][y] = color;
        }
        masksprite(screen, buffer[0], 0, 0, 240, 240, 0xf800);
		refresh(screen);
		clearBuf(screen);
    }  
	free(screen);
	endTP();
	return 0;
}

Spenceboy98 · « **Reply #4 on:** June 18, 2013, 02:04:51 pm »

*BUMP*
Could someone please help? I have no idea why it's doing this.

Matrefeytontias · « **Reply #5 on:** June 18, 2013, 02:35:06 pm »

I can't see your code since my phone is real shit, but seeing at the result it seems that somehow your implementation of the algorithm doesn't work with negative numbers. I'd recommend casting the angle and depth to unsigned int before using the modulo when you get the texels.

Spenceboy98 · « **Reply #6 on:** June 18, 2013, 02:51:37 pm »

It has

Code: [Select]

(unsigned int)(distanceTable[x][y] + shiftX) already, but I made it

Code: [Select]

(unsigned int)((unsigned int)distanceTable[x][y] + shiftX) and there's no change. Any other ideas?

Matrefeytontias · « **Reply #7 on:** June 18, 2013, 03:16:42 pm »

No, I didn't mean that ; how do you calculate x and y from the code you posted ? Those are the ones you need to cast to unsigned int before moduling them.

Spenceboy98 · « **Reply #8 on:** June 18, 2013, 03:26:29 pm »

x and y are just from a for loop:

Code: [Select]

for(x = 0; x < w; x++)
for(y = 0; y < h; y++){
    color=texture[blah][blah];
    buffer[x][y]=color;
}

Augs · « **Reply #9 on:** June 18, 2013, 03:47:48 pm »

I'm not an expert(In fact I have no idea how this works) but it looks to me that you are stretching the bottom of the texture across half the tunnel. Make sure that your variable(One of the texture drawing ones) isn't saying constant.

Matrefeytontias · « **Reply #10 on:** June 18, 2013, 04:02:10 pm »

^ that, but also I was actually asking for the calculations you replaced by "blah"

Spenceboy98 · « **Reply #11 on:** June 18, 2013, 04:12:41 pm »

Here are the values:

Code: [Select]

texture[((unsigned int)(distanceTable[x][y] + shiftX)  % texWidth)][((unsigned int)(angleTable[x][y] + shiftY) % texHeight)];

Matrefeytontias · « **Reply #12 on:** June 18, 2013, 04:21:18 pm »

And that doesn't work ? Weird .__.

Try replacing the cast with abs(), just to be sure.

Spenceboy98 · « **Reply #13 on:** June 18, 2013, 04:25:27 pm »

Quote from: Matrefeytontias on June 18, 2013, 04:21:18 pm

And that doesn't work ? Weird .__.

Try replacing the cast with abs(), just to be sure.

Nope. Still doesn't work.

Matrefeytontias · « **Reply #14 on:** June 19, 2013, 01:02:01 am »

Then be sure that you don't cast to unsigned too early in the calculations.

Can you post the code on pastebin or whatever, that I could look at it ?

Author Topic: [Ndless] Tunnel (Read 27756 times)

Spenceboy98

[Ndless] Tunnel

lkj

Re: [Ndless] Tunnel

DJ Omnimaga

Re: [Ndless] Tunnel

Spenceboy98

Re: [Ndless] Tunnel

Spenceboy98

Re: [Ndless] Tunnel

Matrefeytontias

Re: [Ndless] Tunnel

Spenceboy98

Re: [Ndless] Tunnel

Matrefeytontias

Re: [Ndless] Tunnel

Spenceboy98

Re: [Ndless] Tunnel

Augs

Re: [Ndless] Tunnel

Matrefeytontias

Re: [Ndless] Tunnel

Spenceboy98

Re: [Ndless] Tunnel

Matrefeytontias

Re: [Ndless] Tunnel

Spenceboy98

Re: [Ndless] Tunnel

Matrefeytontias

Re: [Ndless] Tunnel