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/* Microcontroller graphic demo by Pascal Piazzalunga
* admin@serveurperso.com http://www.serveurperso.com
* https://www.youtube.com/watch?v=wyuJ-dqS2to
* Ported to stm32/ChibiOS/glx by Chris Baird.
* It's spinnin' bubbles, man.
* --
* Licencing? Ask Pascal. Let's assume it is freely-distributable and
* modifiable, provided his name is kept in the source.
* --
* Chris Baird,, <cjb@brushtail.apana.org.au> April 2013
*
* Modified Andrew Hannam (inmarket) 2013-04-29 New GFX calls
*/
#include <math.h>
#include "gfx.h"
/* ---------------------------------------------------------------------- */
#define N 1024 /* Number of dots */
#define SCALE 8192
#define INCREMENT 512 /* INCREMENT = SCALE / sqrt(N) * 2 */
#define PI2 6.283185307179586476925286766559
#define background RGB2COLOR(0,0,0)
gU16 width, height;
gI16 sine[SCALE+(SCALE/4)];
gI16 *cosi = &sine[SCALE/4]; /* cos(x) = sin(x+90d)... */
void initialize (void)
{
gU16 i;
/* if you change the SCALE*1.25 back to SCALE, the program will
* occassionally overrun the cosi array -- however this actually
* produces some interesting effects as the BUBBLES LOSE CONTROL!!!!
*/
for (i = 0; i < SCALE+(SCALE/4); i++)
//sine[i] = (-SCALE/2) + (int)(sinf(PI2 * i / SCALE) * sinf(PI2 * i / SCALE) * SCALE);
sine[i] = (int)(sinf(PI2 * i / SCALE) * SCALE);
}
void matrix (gI16 xyz[3][N], gColor col[N])
{
static gU32 t = 0;
gI16 x = -SCALE, y = -SCALE;
gU16 i, s, d;
gU8 red,grn,blu;
#define RED_COLORS (32)
#define GREEN_COLORS (64)
#define BLUE_COLORS (32)
for (i = 0; i < N; i++)
{
xyz[0][i] = x;
xyz[1][i] = y;
d = sqrt(x * x + y * y); /* originally a fastsqrt() call */
s = sine[(t * 30) % SCALE] + SCALE;
xyz[2][i] = sine[(d + s) % SCALE] * sine[(t * 10) % SCALE] / SCALE / 2;
red = (cosi[xyz[2][i] + SCALE / 2] + SCALE) *
(RED_COLORS - 1) / SCALE / 2;
grn = (cosi[(xyz[2][i] + SCALE / 2 + 2 * SCALE / 3) % SCALE] + SCALE) *
(GREEN_COLORS - 1) / SCALE / 2;
blu = (cosi[(xyz[2][i] + SCALE / 2 + SCALE / 3) % SCALE] + SCALE) *
(BLUE_COLORS - 1) / SCALE / 2;
col[i] = ((red << 11) + (grn << 5) + blu);
x += INCREMENT;
if (x >= SCALE) x = -SCALE, y += INCREMENT;
}
t++;
}
void rotate (gI16 xyz[3][N], gU16 angleX, gU16 angleY, gU16 angleZ)
{
gU16 i;
gI16 tmpX, tmpY;
gI16 sinx = sine[angleX], cosx = cosi[angleX];
gI16 siny = sine[angleY], cosy = cosi[angleY];
gI16 sinz = sine[angleZ], cosz = cosi[angleZ];
for (i = 0; i < N; i++)
{
tmpX = (xyz[0][i] * cosx - xyz[2][i] * sinx) / SCALE;
xyz[2][i] = (xyz[0][i] * sinx + xyz[2][i] * cosx) / SCALE;
xyz[0][i] = tmpX;
tmpY = (xyz[1][i] * cosy - xyz[2][i] * siny) / SCALE;
xyz[2][i] = (xyz[1][i] * siny + xyz[2][i] * cosy) / SCALE;
xyz[1][i] = tmpY;
tmpX = (xyz[0][i] * cosz - xyz[1][i] * sinz) / SCALE;
xyz[1][i] = (xyz[0][i] * sinz + xyz[1][i] * cosz) / SCALE;
xyz[0][i] = tmpX;
}
}
void draw(gI16 xyz[3][N], gColor col[N])
{
static gU16 oldProjX[N] = {0};
static gU16 oldProjY[N] = {0};
static gU8 oldDotSize[N] = {0};
gU16 i, projX, projY, projZ, dotSize;
for (i = 0; i < N; i++)
{
projZ = SCALE - (xyz[2][i] + SCALE) / 4;
projX = width / 2 + (xyz[0][i] * projZ / SCALE) / 25;
projY = height / 2 + (xyz[1][i] * projZ / SCALE) / 25;
dotSize = 3 - (xyz[2][i] + SCALE) * 2 / SCALE;
gdispDrawCircle (oldProjX[i], oldProjY[i], oldDotSize[i], background);
if (projX > dotSize &&
projY > dotSize &&
projX < width - dotSize &&
projY < height - dotSize)
{
gdispDrawCircle (projX, projY, dotSize, col[i]);
oldProjX[i] = projX;
oldProjY[i] = projY;
oldDotSize[i] = dotSize;
}
}
}
/* ---------------------------------------------------------------------- */
gI16 angleX = 0, angleY = 0, angleZ = 0;
gI16 speedX = 0, speedY = 0, speedZ = 0;
gI16 xyz[3][N];
gColor col[N];
int main (void)
{
int pass = 0;
gfxInit();
gfxSleepMilliseconds (10);
gdispClear (background); /* glitches.. */
gfxSleepMilliseconds (10);
gdispClear (background); /* glitches.. */
gfxSleepMilliseconds (10);
gdispClear (background); /* glitches.. */
width = (gU16)gdispGetWidth();
height = (gU16)gdispGetHeight();
initialize();
for (;;)
{
matrix(xyz, col);
rotate(xyz, angleX, angleY, angleZ);
draw(xyz, col);
angleX += speedX;
angleY += speedY;
angleZ += speedZ;
if (pass > 400) speedY = 1;
if (pass > 800) speedX = 1;
if (pass > 1200) speedZ = 1;
pass++;
if (angleX >= SCALE) angleX -= SCALE;
else if (angleX < 0) angleX += SCALE;
if (angleY >= SCALE) angleY -= SCALE;
else if (angleY < 0) angleY += SCALE;
if (angleZ >= SCALE) angleZ -= SCALE;
else if (angleZ < 0) angleZ += SCALE;
}
}
/* ---------------------------------------------------------------------- */
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