/// Draw 3D
void Demos::Hedrons(Adafruit_SSD1306& d)
{
if (hdtOn)
{ ++hdt;
if (hdt >= hdtMax)
{ hdt = 0; ++hdCur; // next type
if (hdCur >= hdA) hdCur = 0;
} }
const int u = hdCur;
const float SC = SCa[u]; // scale
float rx=0.f,ry=0.f,rz=0.f, s = SC, ss=1.f;
switch (hdRot) //par rot speed
{ case 0: rx = t*0.0055f; ry = t*0.0065f; rz = t*0.0075f; break;
case 1: rx = t*0.0061f; ry = t*0.0084f; rz = t*0.0077f; break;
case 2: rx = t*0.0067f; ry = t*0.0098f; rz = t*0.0083f;
ss = 1.0f - 0.4f * (abs(cos(t*0.0125f))); break;
case 3: ry = t*0.0060f; rz = t*0.0020f; break;
}
const int NP = NPa[u], NE = NEa[u], NF = NFa[u];
const float* pp = ppA[u];
const uint8_t* ee = eeA[u], *ff = ffA[u];
const float ///par z pos screen scale
fovy = 30.f, zz = 3.f, se = 2.f,
fv = 1.f/tan(fovy*0.5f), // const
cx = cos(rx), sx = sin(rx), cy = cos(ry), sy = sin(ry),
cz = cos(rz), sz = sin(rz),
mx[3][3] = {{1.f,0.f,0.f},{0.f,cx,-sx},{0.f,sx,cx}}, // rot x
my[3][3] = {{cy,0.f,sy},{0.f,1.f,0.f},{-sy,0.f,cy}}, // y
mz[3][3] = {{cz,-sz,0.f},{sz,cz,0.f},{0.f,0.f,1.f}}; // z
// transform all points
int16_t px[NP], py[NP]; int8_t c[NP];
int i, a;
for (i=0,a=0; i < NP; ++i)
{
float x = pp[a++], y = pp[a++], z = pp[a++];
float v[3];
v[0] = mx[0][0]*x +mx[0][1]*y +mx[0][2]*z; // rotate
v[1] = mx[1][0]*x +mx[1][1]*y +mx[1][2]*z;
v[2] = mx[2][0]*x +mx[2][1]*y +mx[2][2]*z;
x = v[0]; y = v[1]; z = v[2];
v[0] = my[0][0]*x +my[0][1]*y +my[0][2]*z;
v[1] = my[1][0]*x +my[1][1]*y +my[1][2]*z;
v[2] = my[2][0]*x +my[2][1]*y +my[2][2]*z;
x = v[0]; y = v[1]; z = v[2];
v[0] = mz[0][0]*x +mz[0][1]*y +mz[0][2]*z;
v[1] = mz[1][0]*x +mz[1][1]*y +mz[1][2]*z;
v[2] = mz[2][0]*x +mz[2][1]*y +mz[2][2]*z;
x = v[0] * s; y = v[1] * s; z = v[2] * s + ss*zz;
px[i] = H/2 * se * (fv * x / -z) +W/2; // pos 3d to 2d
py[i] = H/2 * se * (fv * y / -z) +H/2;
c[i] = z < 0.9f ? -1 : (z < zz ? 1 : 0);
if (px[i]<0 || px[i]>=W || py[i]<0 || py[i]>=H)
c[i] = -1; // outside
//c[i] = z < zz ? 1 : 0;
//d.drawPixel(px[i], py[i],WHITE);
}
// draw far/covered edges --
for (i=0,a=0; i < NE; ++i)
{
int e0 = ee[a++], e1 = ee[a++];
int8_t cc = max(c[e0],c[e1]);
if (cc==0)
d.drawLine( px[e0],py[e0], px[e1],py[e1], WHITE);
}
// draw far faces /|
if (ff)
for (i=0,a=0; i < NF; ++i)
{
int f0 = ff[a++], f1 = ff[a++], f2 = ff[a++];
int8_t cc = min(c[f0],c[f1]); cc = min(cc,c[f2]);
if (cc==0)
d.fillTriangle( px[f0],py[f0], px[f1],py[f1], px[f2],py[f2], WHITE);
}
// dither 2 full screen --------
uint8_t* buf = d.getBuffer();
for (i=0; i < W*H/8; i+=2) buf[i] &= 0xAA;
for (i=1; i < W*H/8; i+=2) buf[i] &= 0x55;
// draw near/visible edges --
for (i=0,a=0; i < NE; ++i)
{
int e0 = ee[a++], e1 = ee[a++];
int8_t cc = max(c[e0],c[e1]);
if (cc>0)
d.drawLine( px[e0],py[e0], px[e1],py[e1], WHITE);
}
// draw near faces /|
if (ff)
for (i=0,a=0; i < NF; ++i)
{
int f0 = ff[a++], f1 = ff[a++], f2 = ff[a++];
int8_t cc = min(c[f0],c[f1]); cc = min(cc,c[f2]);
if (cc>0)
d.fillTriangle( px[f0],py[f0], px[f1],py[f1], px[f2],py[f2], WHITE);
}
if (iInfo > 0)
{
d.setCursor(0,8);
d.print("Cur "); d.println(hdCur);
d.print("Rot "); d.println(hdRot);
if (hdtOn) d.println("On");
}
++t;
delay(8);
}
