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Just another update

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Ingy döt Net 2015-02-20 00:35:01 -05:00
parent a25938f123
commit 00a190b0a6
6591 changed files with 94363 additions and 23227 deletions
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44
Task/Xiaolin-Wus-line-algorithm/D/xiaolin-wus-line-algorithm.d
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@ -4,17 +4,19 @@ import std.math, std.algorithm, grayscale_image;
void aaLine(Color)(ref Image!Color img,
double x1, double y1,
double x2, double y2,
in Color color) /*pure*/ nothrow {
in Color color) pure nothrow @safe @nogc {
// Straight translation of Wikipedia pseudocode.
static double round(in double x) pure nothrow {
// std.math.round is not pure. **
static double round(in double x) pure nothrow @safe @nogc {
return floor(x + 0.5);
}
static double fpart(in double x) pure nothrow {
static double fpart(in double x) pure nothrow @safe @nogc {
return x - x.floor;
}
static double rfpart(in double x) pure nothrow {
static double rfpart(in double x) pure nothrow @safe @nogc {
return 1 - fpart(x);
}
@ -24,7 +26,7 @@ void aaLine(Color)(ref Image!Color img,
immutable ay = dy.abs;
static Color mixColors(in Color c1, in Color c2, in double p)
pure nothrow {
pure nothrow @safe @nogc {
static if (is(Color == RGB))
return Color(cast(ubyte)(c1.r * p + c2.r * (1 - p)),
cast(ubyte)(c1.g * p + c2.g * (1 - p)),
@ -35,23 +37,23 @@ void aaLine(Color)(ref Image!Color img,
}
// Plot function set here to handle the two cases of slope.
void delegate(ref Image!Color img, in int, in int, in double)
pure nothrow plot;
void function(ref Image!Color, in int, in int, in double, in Color)
pure nothrow @safe @nogc plot;
if (ax < ay) {
swap(x1, y1);
swap(x2, y2);
swap(dx, dy);
//plot = (img, x, y, p) {
plot = (ref Image!Color img, x, y, p) {
//plot = (img, x, y, p, col) {
plot = (ref img, x, y, p, col) {
assert(p >= 0.0 && p <= 1.0);
img[y, x] = mixColors(color, img[y, x], p);
img[y, x] = mixColors(col, img[y, x], p);
};
} else {
//plot = (img, x, y, p) {
plot = (ref Image!Color img, x, y, p) {
//plot = (img, x, y, p, col) {
plot = (ref img, x, y, p, col) {
assert(p >= 0.0 && p <= 1.0);
img[x, y] = mixColors(color, img[x, y], p);
img[x, y] = mixColors(col, img[x, y], p);
};
}
@ -62,31 +64,31 @@ void aaLine(Color)(ref Image!Color img,
immutable gradient = dy / dx;
// Handle first endpoint.
auto xEnd = x1.round; // Not pure.
auto xEnd = round(x1);
auto yEnd = y1 + gradient * (xEnd - x1);
auto xGap = rfpart(x1 + 0.5);
// This will be used in the main loop.
immutable xpxl1 = cast(int)xEnd;
immutable ypxl1 = cast(int)yEnd.floor;
plot(img, xpxl1, ypxl1, rfpart(yEnd) * xGap);
plot(img, xpxl1, ypxl1 + 1, fpart(yEnd) * xGap);
plot(img, xpxl1, ypxl1, rfpart(yEnd) * xGap, color);
plot(img, xpxl1, ypxl1 + 1, fpart(yEnd) * xGap, color);
// First y-intersection for the main loop.
auto yInter = yEnd + gradient;
// Handle second endpoint.
xEnd = x2.round;
xEnd = round(x2);
yEnd = y2 + gradient * (xEnd - x2);
xGap = fpart(x2 + 0.5);
// This will be used in the main loop.
immutable xpxl2 = cast(int)xEnd;
immutable ypxl2 = cast(int)yEnd.floor;
plot(img, xpxl2, ypxl2, rfpart(yEnd) * xGap);
plot(img, xpxl2, ypxl2 + 1, fpart(yEnd) * xGap);
plot(img, xpxl2, ypxl2, rfpart(yEnd) * xGap, color);
plot(img, xpxl2, ypxl2 + 1, fpart(yEnd) * xGap, color);
// Main loop.
foreach (immutable x; xpxl1 + 1 .. xpxl2) {
plot(img, x, cast(int)yInter.floor, rfpart(yInter));
plot(img, x, cast(int)yInter.floor + 1, fpart(yInter));
plot(img, x, cast(int)yInter.floor, rfpart(yInter), color);
plot(img, x, cast(int)yInter.floor + 1, fpart(yInter), color);
yInter += gradient;
}
}