FITD/FitdLib/polys.cpp

141 lines
3.7 KiB
C++

#include "common.h"
void hline(int x1, int x2, int y, unsigned char c);
void line(int x1, int y1, int x2, int y2, unsigned char c);
void pixel(int x, int y, unsigned char c);
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#define SCREENHEIGHT 200
#define MAXPTS 10
#define putdot(x,y) if ((y >= 0) && (y < SCREENHEIGHT)) dots[y][counters[y]++] = x;
void swapFunc(int* a, int* b);
#define swap(a,b) (swapFunc(&a,&b))
void fillpoly(s16 * datas, int n, unsigned char c) {
static int dots[SCREENHEIGHT][MAXPTS];
static int counters[SCREENHEIGHT];
s16 x1, y1, x2, y2;
int i, j, k, dir = -2;
double step, curx;
if (n <= 2) {
switch (n) {
case 0:
return;
case 1:
pixel(datas[0], datas[1], c);
return;
case 2:
line(datas[0], datas[1], datas[2], datas[3], c);
return;
}
}
// Reinit array counters
for (i = 0; i < SCREENHEIGHT; i++) {
counters[i] = 0;
}
// Drawing lines
x2 = datas[n * 2 - 2];
y2 = datas[n * 2 - 1];
for (i = 0; i < n; i++) {
x1 = x2;
y1 = y2;
x2 = datas[i * 2];
y2 = datas[i * 2 + 1];
// line(x1, y1, x2, y2, c);
// continue;
if (y1 == y2) {
// printf("Horizontal line. x1: %i, y1: %i, x2: %i, y2: %i\n", x1, y1, x2, y2);
if (!dir)
continue;
putdot(x1, y1);
dir = 0;
continue;
}
step = (double) (x2 - x1) / (y2 - y1);
// printf("x1: %i, y1 = %i, x2 = %i, y2 = %i, step: %f\n", x1, y1, x2, y2, step);
curx = x1;
if (y1 < y2) {
for (j = y1; j < y2; j++, curx += step) {
// printf("j = %i, curx = %f\n", j, curx);
putdot((int)(curx + 0.5), j);
}
if (dir == -1) {
// printf("Adding extra (%i, %i)\n", x1, y1);
putdot(x1, y1);
}
dir = 1;
} else {
for (j = y1; j > y2; j--, curx -= step) {
// printf("j = %i, curx = %f\n", j, curx);
putdot((int)(curx + 0.5), j);
}
if (dir == 1) {
// printf("Adding extra (%i, %i)\n", x1, y1);
putdot(x1, y1);
}
dir = -1;
}
}
x1 = x2;
y1 = y2;
x2 = datas[0];
y2 = datas[1];
if (((y1 < y2) && (dir == -1)) || ((y1 > y2) && (dir == 1)) || ((y1 == y2) && (dir == 0))) {
// printf("Adding final extra (%i, %i)\n", x1, y1);
putdot(x1, y1);
}
// NOTE: all counters should be even now. If not, this is a bad (C) thing :-P
// Sorting datas
for (i = 0; i < SCREENHEIGHT; i++) {
// Very bad sorting... but arrays are very small (0, 2 or 4), so it's no quite use...
for (j = 0; j < (counters[i] - 1); j++) {
for (k = 0; k < (counters[i] - 1); k++) {
if (dots[i][k] > dots[i][k + 1])
swap(dots[i][k], dots[i][k + 1]);
}
}
}
// Drawing.
for (i = 0; i < SCREENHEIGHT; i++) {
if (counters[i]) {
// printf("%i dots on line %i\n", counters[i], i);
for (j = 0; j < counters[i] - 1; j += 2) {
// printf("Drawing line (%i, %i)-%i\n", dots[i][j], dots[i][j + 1], i);
hline(dots[i][j], dots[i][j + 1], i, c);
#ifdef DEBUGGING_POLYS
if ((!dots[i][j]) || !(dots[i][j + 1])) {
printf("fillpoly: BLARGH!\n");
assert(0);
}
#endif
}
}
}
}
#undef swap