307 lines
6.0 KiB
C++
307 lines
6.0 KiB
C++
/*
|
|
From ucg, modified for use with all my libraries.
|
|
IMPORTANT! You need my modified Adafruit_GFX library!
|
|
https://github.com/sumotoy/Adafruit_GFX/
|
|
*/
|
|
|
|
|
|
|
|
#include <SPI.h>
|
|
#include <Adafruit_GFX.h>
|
|
#include <TFT_ILI9163C.h>
|
|
|
|
#ifndef _ADAFRUIT_GFX_VARIANT
|
|
#error you need the modified Adafruit_GFX library!
|
|
#endif
|
|
|
|
#define __CS 10
|
|
#define __DC 6
|
|
|
|
TFT_ILI9163C tft = TFT_ILI9163C(__CS, __DC);
|
|
|
|
struct pt3d
|
|
{
|
|
int x, y, z;
|
|
};
|
|
|
|
struct surface
|
|
{
|
|
uint8_t p[4];
|
|
int16_t z;
|
|
};
|
|
|
|
struct pt2d
|
|
{
|
|
int x, y;
|
|
unsigned is_visible;
|
|
};
|
|
|
|
|
|
// define the point at which the observer looks, 3d box will be centered there
|
|
#define MX (tft.width()/2)
|
|
#define MY (tft.height()/2)
|
|
|
|
// define a value that corresponds to "1"
|
|
#define U 100
|
|
|
|
// eye to screen distance (fixed)
|
|
#define ZS U
|
|
|
|
// cube edge length is 2*U
|
|
struct pt3d cube[8] =
|
|
{
|
|
{ -U, -U, U},
|
|
{ U, -U, U},
|
|
{ U, -U, -U},
|
|
{ -U, -U, -U},
|
|
{ -U, U, U},
|
|
{ U, U, U},
|
|
{ U, U, -U},
|
|
{ -U, U, -U},
|
|
};
|
|
|
|
// define the surfaces
|
|
struct surface cube_surface[6] =
|
|
{
|
|
{ {0, 1, 2, 3}, 0 }, // bottom
|
|
{ {4, 5, 6, 7}, 0 }, // top
|
|
{ {0, 1, 5, 4}, 0 }, // back
|
|
|
|
{ {3, 7, 6, 2}, 0 }, // front
|
|
{ {1, 2, 6, 5}, 0 }, // right
|
|
{ {0, 3, 7, 4}, 0 }, // left
|
|
};
|
|
|
|
// define some structures for the copy of the box, calculation will be done there
|
|
struct pt3d cube2[8];
|
|
struct pt2d cube_pt[8];
|
|
|
|
// will contain a rectangle border of the box projection into 2d plane
|
|
int x_min, x_max;
|
|
int y_min, y_max;
|
|
|
|
const int16_t sin_tbl[65] = {
|
|
0, 1606, 3196, 4756, 6270, 7723, 9102, 10394, 11585, 12665, 13623, 14449, 15137, 15679, 16069, 16305, 16384, 16305, 16069, 15679,
|
|
15137, 14449, 13623, 12665, 11585, 10394, 9102, 7723, 6270, 4756, 3196, 1606, 0, -1605, -3195, -4755, -6269, -7722, -9101, -10393,
|
|
-11584, -12664, -13622, -14448, -15136, -15678, -16068, -16304, -16383, -16304, -16068, -15678, -15136, -14448, -13622, -12664, -11584, -10393, -9101, -7722,
|
|
-6269, -4755, -3195, -1605, 0
|
|
};
|
|
|
|
const int16_t cos_tbl[65] = {
|
|
16384, 16305, 16069, 15679, 15137, 14449, 13623, 12665, 11585, 10394, 9102, 7723, 6270, 4756, 3196, 1606, 0, -1605, -3195, -4755,
|
|
-6269, -7722, -9101, -10393, -11584, -12664, -13622, -14448, -15136, -15678, -16068, -16304, -16383, -16304, -16068, -15678, -15136, -14448, -13622, -12664,
|
|
-11584, -10393, -9101, -7722, -6269, -4755, -3195, -1605, 0, 1606, 3196, 4756, 6270, 7723, 9102, 10394, 11585, 12665, 13623, 14449,
|
|
15137, 15679, 16069, 16305, 16384
|
|
};
|
|
|
|
|
|
void copy_cube(void)
|
|
{
|
|
uint8_t i;
|
|
for (i = 0; i < 8; i++)
|
|
{
|
|
cube2[i] = cube[i];
|
|
}
|
|
}
|
|
|
|
void rotate_cube_y(uint16_t w)
|
|
{
|
|
uint8_t i;
|
|
int16_t x, z;
|
|
/*
|
|
x' = x * cos(w) + z * sin(w)
|
|
z' = - x * sin(w) + z * cos(w)
|
|
*/
|
|
for (i = 0; i < 8; i++)
|
|
{
|
|
x = ((int32_t)cube2[i].x * (int32_t)cos_tbl[w] + (int32_t)cube2[i].z * (int32_t)sin_tbl[w]) >> 14;
|
|
z = (-(int32_t)cube2[i].x * (int32_t)sin_tbl[w] + (int32_t)cube2[i].z * (int32_t)cos_tbl[w]) >> 14;
|
|
//printf("%d: %d %d --> %d %d\n", i, cube2[i].x, cube2[i].z, x, z);
|
|
cube2[i].x = x;
|
|
cube2[i].z = z;
|
|
}
|
|
}
|
|
|
|
void rotate_cube_x(uint16_t w)
|
|
{
|
|
uint8_t i;
|
|
int16_t y, z;
|
|
for (i = 0; i < 8; i++)
|
|
{
|
|
y = ((int32_t)cube2[i].y * (int32_t)cos_tbl[w] + (int32_t)cube2[i].z * (int32_t)sin_tbl[w]) >> 14;
|
|
z = (-(int32_t)cube2[i].y * (int32_t)sin_tbl[w] + (int32_t)cube2[i].z * (int32_t)cos_tbl[w]) >> 14;
|
|
cube2[i].y = y;
|
|
cube2[i].z = z;
|
|
}
|
|
}
|
|
|
|
void trans_cube(uint16_t z)
|
|
{
|
|
uint8_t i;
|
|
for (i = 0; i < 8; i++)
|
|
{
|
|
cube2[i].z += z;
|
|
}
|
|
}
|
|
|
|
void reset_min_max(void)
|
|
{
|
|
x_min = 0x07fff;
|
|
y_min = 0x07fff;
|
|
x_max = -0x07fff;
|
|
y_max = -0x07fff;
|
|
}
|
|
|
|
// calculate xs and ys from a 3d value
|
|
void convert_3d_to_2d(struct pt3d *p3, struct pt2d *p2)
|
|
{
|
|
int32_t t;
|
|
p2->is_visible = 1;
|
|
if (p3->z >= ZS)
|
|
{
|
|
t = ZS;
|
|
t *= p3->x;
|
|
t <<= 1;
|
|
t /= p3->z;
|
|
if (t >= -MX && t <= MX - 1)
|
|
{
|
|
t += MX;
|
|
p2->x = t;
|
|
|
|
if (x_min > t) x_min = t;
|
|
if (x_max < t) x_max = t;
|
|
|
|
t = ZS;
|
|
t *= p3->y;
|
|
t <<= 1;
|
|
t /= p3->z;
|
|
if (t >= -MY && t <= MY - 1)
|
|
{
|
|
t += MY;
|
|
p2->y = t;
|
|
if (y_min > t) y_min = t;
|
|
if (y_max < t) y_max = t;
|
|
}
|
|
else
|
|
{
|
|
p2->is_visible = 0;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
p2->is_visible = 0;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
p2->is_visible = 0;
|
|
}
|
|
}
|
|
|
|
void convert_cube(void)
|
|
{
|
|
uint8_t i;
|
|
reset_min_max();
|
|
for (i = 0; i < 8; i++)
|
|
{
|
|
convert_3d_to_2d(cube2 + i, cube_pt + i);
|
|
}
|
|
}
|
|
|
|
void calculate_z(void)
|
|
{
|
|
uint8_t i, j;
|
|
uint16_t z;
|
|
for (i = 0; i < 6; i++)
|
|
{
|
|
z = 0;
|
|
for (j = 0; j < 4; j++)
|
|
{
|
|
z += cube2[cube_surface[i].p[j]].z;
|
|
}
|
|
z /= 4;
|
|
cube_surface[i].z = z;
|
|
//printf("%d: z=%d\n", i, z);
|
|
}
|
|
}
|
|
|
|
void draw_cube(void)
|
|
{
|
|
uint8_t i, ii;
|
|
uint8_t skip_cnt = 3; /* it is known, that the first 3 surfaces are invisible */
|
|
int16_t z, z_upper;
|
|
uint16_t color;
|
|
|
|
z_upper = 32767;
|
|
for (;;)
|
|
{
|
|
ii = 6;
|
|
z = -32767;
|
|
for (i = 0; i < 6; i++)
|
|
{
|
|
if (cube_surface[i].z <= z_upper)
|
|
{
|
|
if (z < cube_surface[i].z)
|
|
{
|
|
z = cube_surface[i].z;
|
|
ii = i;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (ii >= 6) break;
|
|
z_upper = cube_surface[ii].z;
|
|
cube_surface[ii].z++;
|
|
|
|
if (skip_cnt > 0)
|
|
{
|
|
skip_cnt--;
|
|
}
|
|
else
|
|
{
|
|
color = tft.Color565(((ii + 1) & 1) * 255, (((ii + 1) >> 1) & 1) * 255, (((ii + 1) >> 2) & 1) * 255);
|
|
tft.fillQuad(
|
|
cube_pt[cube_surface[ii].p[0]].x, cube_pt[cube_surface[ii].p[0]].y,
|
|
cube_pt[cube_surface[ii].p[1]].x, cube_pt[cube_surface[ii].p[1]].y,
|
|
cube_pt[cube_surface[ii].p[2]].x, cube_pt[cube_surface[ii].p[2]].y,
|
|
cube_pt[cube_surface[ii].p[3]].x, cube_pt[cube_surface[ii].p[3]].y, color);
|
|
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
|
|
void calc_and_draw(uint16_t w, uint16_t v)
|
|
{
|
|
|
|
copy_cube();
|
|
rotate_cube_y(w);
|
|
rotate_cube_x(v);
|
|
trans_cube(U * 8);
|
|
convert_cube();
|
|
calculate_z();
|
|
draw_cube();
|
|
}
|
|
|
|
|
|
void setup(void)
|
|
{
|
|
tft.begin();
|
|
}
|
|
|
|
uint16_t w = 0;
|
|
uint16_t v = 0;
|
|
|
|
void loop(void)
|
|
{
|
|
calc_and_draw(w, v >> 3);
|
|
v += 3;
|
|
v &= 511;
|
|
w++;
|
|
w &= 63;
|
|
delay(10);
|
|
tft.fillRect(x_min, y_min, x_max - x_min + 3, y_max - y_min + 3, 0x0000);
|
|
}
|
|
|