/**
* Convert Hue Saturation Lightness value to RGB.
*
* \param hue Hue in degrees 0..360
* \param sat Saturation value in percent 0..100
* \param lit Lightness value in percent 0..100
* \param r red component
* \param g green component
* \param b blue component
*/
static void HSL_to_RGB(css_fixed hue, css_fixed sat, css_fixed lit, uint8_t *r, uint8_t *g, uint8_t *b)
{
css_fixed min_rgb, max_rgb, chroma;
css_fixed relative_hue, scaled_hue, mid1, mid2;
int sextant;
#define ORGB(R, G, B) \
*r = FIXTOINT(FDIV(FMUL((R), F_255), F_100)); \
*g = FIXTOINT(FDIV(FMUL((G), F_255), F_100)); \
*b = FIXTOINT(FDIV(FMUL((B), F_255), F_100))
/* If saturation is zero there is no hue and r = g = b = lit */
if (sat == INTTOFIX(0)) {
ORGB(lit, lit, lit);
return;
}
/* Compute max(r,g,b) */
if (lit <= INTTOFIX(50)) {
max_rgb = FDIV(FMUL(lit, FADD(sat, F_100)), F_100);
} else {
max_rgb = FDIV(FSUB(FMUL(FADD(lit, sat), F_100), FMUL(lit, sat)), F_100);
}
/* Compute min(r,g,b) */
min_rgb = FSUB(FMUL(lit, INTTOFIX(2)), max_rgb);
/* We know that the value of at least one of the components is
* max(r,g,b) and that the value of at least one of the other
* components is min(r,g,b).
*
* We can determine which components have these values by
* considering which the sextant of the hexcone the hue lies
* in:
*
* Sextant: max(r,g,b): min(r,g,b):
*
* 0 r b
* 1 g b
* 2 g r
* 3 b r
* 4 b g
* 5 r g
*
* Thus, we need only compute the value of the third component
*/
/* Chroma is the difference between min and max */
chroma = FSUB(max_rgb, min_rgb);
/* Compute which sextant the hue lies in (truncates result) */
hue = FDIV(FMUL(hue, INTTOFIX(6)), F_360);
sextant = FIXTOINT(hue);
/* Compute offset of hue from start of sextant */
relative_hue = FSUB(hue, INTTOFIX(sextant));
/* Scale offset by chroma */
scaled_hue = FMUL(relative_hue, chroma);
/* Compute potential values of the third colour component */
mid1 = FADD(min_rgb, scaled_hue);
mid2 = FSUB(max_rgb, scaled_hue);
/* Populate result */
switch (sextant) {
case 0: ORGB(max_rgb, mid1, min_rgb); break;
case 1: ORGB(mid2, max_rgb, min_rgb); break;
case 2: ORGB(min_rgb, max_rgb, mid1); break;
case 3: ORGB(min_rgb, mid2, max_rgb); break;
case 4: ORGB(mid1, min_rgb, max_rgb); break;
case 5: ORGB(max_rgb, min_rgb, mid2); break;
}
#undef ORGB
}
int main(int argc, char *argv[]) {
E_RT_init(argc, argv);
JMP(begin);
Label0: R005=ADD(R000,2);
STI(R001, R000);
R000=SUB(R000,1);
MOVI(R000, R001);
LDI(R005, R008);
R005=ADD(R005,1);
LDF(R005, F001);
R005=ADD(R005,1);
MOVIF(R008, F003);
MOVIF(R008, F006);
F005=FADD(F006,F001);
MOVF(F005, F008);
R010=ADD(R008,1);
MOVI(R010, R011);
MOVI(R010, R012);
MOVIF(R008, F010);
MOVF(F005, F011);
while_1_start: JMPC(GT(1000, R008), while_1_begin);
JMP(while_1_end);
while_1_begin: MOVIF(R008, F013);
MOVIF(R008, F014);
F008=FADD(F014,F001);
F001=FMUL(F001,2.0);
R008=ADD(R008,100);
JMP(while_1_start);
while_1_end: PRTF(F008);
PRTS(R007);
MOVI(R008, R002);
JMP(Label1);
Label1: MOVI(R001, R000);
R000=ADD(R000,1);
LDI(R000, R001);
R000=ADD(R000,1);
LDI(R000, R004);
R000=ADD(R000,2);
JMPI(R004);
eventLabel_a: INI(R010);
INF(F013);
STI(R010, R000);
R000=SUB(R000,1);
STF(F013, R000);
R000=SUB(R000,1);
STF(F013, R000);
R000=SUB(R000,1);
STI(R010, R000);
R000=SUB(R000,1);
MOVL(Label2, R004);
STI(R004, R000);
R000=SUB(R000,1);
JMP(Label0);
Label2: MOVI(R002, R006);
R000=ADD(R000,1);
LDF(R000, F013);
R000=ADD(R000,1);
LDI(R000, R010);
JMP(EventMStart);
begin: MOVI(10000, R000);
MOVI(0, R006);
MOVS("\n", R007);
IN(R010);
IN(R010);
IN(R010);
EventMStart: IN(R010);
JMPC(GT(64, R010), EventMOut);
JMPC(EQ(97, R010), eventLabel_a);
JMP(EventMStart);
EventMOut: PRTS("\nDone\n");
E_RT_exit(); return 0;
}