cos2000v2/lib/2d.c

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/*******************************************************************************/
/* COS2000 - Compatible Operating System - LGPL v3 - Hord<72> Nicolas */
/* */
#include "types.h"
#include "vga.h"
#include "video.h"
#include "2d.h"
#include "math.h"
/******************************************************************************/
/* Affiche une ligne entre les points sp<73>cifi<66>s */
void linev(vertex2d * A, vertex2d * B, u8 color)
{
line(A->x, A->y, B->x, B->y, color);
}
void line(u32 x1, u32 y1, u32 x2, u32 y2, u8 color)
{
s32 dx, dy, sdx, sdy;
u32 i, dxabs, dyabs, x, y, px, py;
dx = x2 - x1; /* distance horizontale de la line */
dy = y2 - y1; /* distance verticale de la line * */
dxabs = abs(dx);
dyabs = abs(dy);
sdx = sgn(dx);
sdy = sgn(dy);
x = dyabs >> 1;
y = dxabs >> 1;
px = x1;
py = y1;
writepxl(px, py, color);
if (dxabs >= dyabs) { /* la ligne est plus horizontale que verticale */
for (i = 0; i < dxabs; i++) {
y += dyabs;
if (y >= dxabs) {
y -= dxabs;
py += sdy;
}
px += sdx;
writepxl(px, py, color);
}
} else { /* la ligne est plus verticale que horizontale */
for (i = 0; i < dyabs; i++) {
x += dxabs;
if (x >= dyabs) {
x -= dyabs;
px += sdx;
}
py += sdy;
writepxl(px, py, color);
}
}
}
/******************************************************************************/
/* Affiche un triangle rempli entre les points sp<73>cifi<66>s */
void trianglefilled(vertex2d * AA, vertex2d * BB, vertex2d * CC, u8 color)
{
vertex2d *A, *B, *C, *TEMP;
u32 a, b, y, last;
int dx1, dx2, dx3, dy1, dy2, dy3, sa, sb;
A = AA;
B = BB;
C = CC;
while (A->y > B->y || B->y > C->y || A->y == C->y) {
if (A->y > B->y)
swapvertex(A, B);
if (B->y > C->y)
swapvertex(B, C);
if (A->y > C->y)
swapvertex(A, C);
}
if (A->y == C->y) { //meme ligne
a = b = A->x;
if (B->x < a)
a = B->x;
else if (B->x > b)
b = B->x;
if (C->x < a)
a = C->x;
else if (C->x > b)
b = C->x;
hline(a, b, A->y, color);
return;
}
dx1 = B->x - A->x;
dy1 = B->y - A->y;
dx2 = C->x - A->x;
dy2 = C->y - A->y;
dx3 = C->x - B->x;
dy3 = C->y - B->y;
sa = 0;
sb = 0;
if (B->y == C->y)
last = B->y;
else
last = B->y - 1;
for (y = A->y; y <= last; y++) {
a = A->x + sa / dy1;
b = A->x + sb / dy2;
sa += dx1;
sb += dx2;
hline(a, b, y, color);
}
sa = dx3 * (y - B->y);
sb = dx2 * (y - A->y);
for (; y <= C->y; y++) {
a = B->x + sa / dy3;
b = A->x + sb / dy2;
sa += dx3;
sb += dx2;
hline(a, b, y, color);
}
}
void swapvertex(vertex2d * A, vertex2d * B)
{
vertex2d temp = *A;
*A = *B;
*B = temp;
}
/******************************************************************************/
/* Affiche un triangle entre les points sp<73>cifi<66>s */
void triangle(vertex2d * AA, vertex2d * BB, vertex2d * CC, u8 color)
{
line(AA->x, AA->y, BB->x, BB->y, color);
line(BB->x, BB->y, CC->x, CC->y, color);
line(CC->x, CC->y, AA->x, AA->y, color);
}