void a_platform_api__drawLine(int X1, int Y1, int X2, int Y2)
{
int x = a_math_min(X1, X2);
int y = a_math_min(Y1, Y2);
int w = a_math_abs(X2 - X1) + 1;
int h = a_math_abs(Y2 - Y1) + 1;
if(!a_screen_boxOnClip(x, y, w, h)
|| !cohen_sutherland_clip(&X1, &Y1, &X2, &Y2)) {
return;
}
g_draw_line(X1, Y1, X2, Y2);
}
trace_match
line_do_action(int x1, int y1, int x2, int y2, texture_info * tex, VALUE hash_arg,
texplay_sync sync_mode, bool primary, action_struct * payload)
{
int x, y, W, H, F;
int xinc, yinc;
action_struct cur;
int thickness = 1;
bool has_trace = false;
rgba trace_color;
trace_mode_type trace_mode = no_mode;
if(has_optional_hash_arg(hash_arg, "thickness"))
thickness = NUM2INT(get_from_hash(hash_arg, "thickness"));
if(has_optional_hash_arg(hash_arg, "trace") && primary) {
VALUE trace_hash = get_from_hash(hash_arg, "trace");
/* we're tracing (not drawing) */
has_trace = true;
/* since we're not drawing, no need to sync */
sync_mode = no_sync;
if(has_optional_hash_arg(trace_hash, "until_color")) {
VALUE c = get_from_hash(trace_hash, "until_color");
trace_color = convert_rb_color_to_rgba(c);
trace_mode = until_color;
}
else if(has_optional_hash_arg(trace_hash, "while_color")) {
VALUE c = get_from_hash(trace_hash, "while_color");
trace_color = convert_rb_color_to_rgba(c);
trace_mode = while_color;
}
}
draw_prologue(&cur, tex, x1, y1,
x2, y2, &hash_arg, sync_mode, primary, &payload);
/* clip the line */
cohen_sutherland_clip(&x1, &y1, &x2, &y2, 0, 0, tex->width - 1, tex->height - 1);
W = ABS(x2 - x1);
H = ABS(y2 - y1);
if(x1 < x2)
xinc = 1;
else
xinc = -1;
if(y1 < y2)
yinc = 1;
else
yinc = -1;
x = x1;
y = y1;
if(W >= H) {
F = 2 * H - W;
while(x != x2) {
if(thickness <= 1) {
if(!has_trace)
set_pixel_color_with_style(payload, tex, x, y);
else {
rgba c = get_pixel_color(tex, x, y);
if (is_trace_match(payload, c, trace_color, trace_mode))
return (trace_match) { x, y, c };
}
}
else {
set_hash_value(hash_arg, "fill", Qtrue);
circle_do_action(x, y, thickness / 2, tex, hash_arg, no_sync, false, payload);
}
if(F < 0)
F += 2 * H;
else {
F += 2 * (H - W);
y += yinc;
}
x += xinc;
}
}
else {
F = 2 * W - H;
while(y != y2 ) {
if(thickness <= 1) {
if(!has_trace)
set_pixel_color_with_style(payload, tex, x, y);
else {
rgba c = get_pixel_color(tex, x, y);
if (is_trace_match(payload, c, trace_color, trace_mode))
return (trace_match) { x, y, c };
}
}
else {
set_hash_value(hash_arg, "fill", Qtrue);
circle_do_action(x, y, thickness / 2, tex, hash_arg, no_sync, false, payload);
}
if(F < 0)
F += 2 * W;
else {
F += 2 * (W - H);
x += xinc;
}
y += yinc;
}
}
if(thickness <= 1) {
if(!has_trace)
set_pixel_color_with_style(payload, tex, x2, y2);
else {
rgba c = get_pixel_color(tex, x, y);
if (is_trace_match(payload, c, trace_color, trace_mode))
return (trace_match) { x, y, c };
}
}
else {
set_hash_value(hash_arg, "fill", Qtrue);
circle_do_action(x2, y2, thickness / 2, tex, hash_arg, no_sync, false, payload);
}
draw_epilogue(&cur, tex, primary);
return (trace_match) { .x = -9999, .y = -9999, .color = not_a_color_v };
}
/** end line **/
/** polyline algorithm **/
/* used by both polyline and bezier */
#define SIMPLE_FORMAT 0
#define POINT_FORMAT 1
/* calculate a single point */
static void
polyline_point(VALUE points, int k, int * x, int * y, int format, int draw_offset_x,
int draw_offset_y)
{
int xy_index;
switch(format) {
case POINT_FORMAT:
*x = NUM2INT(point_x(get_from_array(points, k))) + draw_offset_x;
*y = NUM2INT(point_y(get_from_array(points, k))) + draw_offset_y;
break;
case SIMPLE_FORMAT:
xy_index = k * 2;
*x = NUM2INT(get_from_array(points, xy_index)) + draw_offset_x;
*y = NUM2INT(get_from_array(points, xy_index + 1)) + draw_offset_y;
break;
default:
rb_raise(rb_eArgError, "pixel format must be either POINT_FORMAT or SIMPLE_FORMAT");
}
}
