Draw a sphere: Difference between revisions

Line 620:

<lang d>import std.stdio, std.math, std.algorithm, std.numeric;

alias double[3] V3;

alias V3 = double[3];

V3 light = [30, 30, -50];

immutable light = normalize([30.0, 30.0, -50.0]);

~~void~~ normalize(~~ref~~ V3 v) pure {

V3 normalize(V3 v) pure @nogc {

v[] /= dotProduct(v, v) ^^ 0.5;

return v;

}

double dot(in ref V3 x, in ref V3 y) pure nothrow {

double dot(in ref V3 x, in ref V3 y) pure nothrow @nogc {

immutable double d = dotProduct(x, y);

return d < 0 ? -d : 0;

}

void drawSphere(in double R, in double k, in double ambient) {

void drawSphere(in double R, in double k, in double ambient)/*@nogc*/ {

enum shades = ".:!*oe&#%@";

foreach (~~int~~ i; cast(int)floor(-R) .. cast(int)ceil(R) + 1) {

foreach (immutable i; cast(int)floor(-R) .. cast(int)ceil(R) + 1) {

immutable double x = i + 0.5;

foreach (~~int~~ j; cast(int)floor(-2*R)..~~cast(int)ceil(2*R)+1){~~

foreach (immutable j; cast(int)floor(-2 * R) ..

cast(int)ceil(2 * R) + 1) {

immutable double y = j / 2. + 0.5;

if (x ^^ 2 + y ^^ 2 <= R ^^ 2) {

V3 vec = [x, y, (R^^2 - x^^2 - y^^2) ^^ 0.5];

immutable vec = [x, y, (R^^2 - x^^2 - y^^2) ^^ 0.5]

~~vec~~.normalize();

.normalize;

immutable double b = dot(light, vec) ^^ k + ambient;

int intensity = cast(int)((1-b) * (shades.length-1));

int intensity = cast(int)((1 - b) * (shades.length-1));

intensity = min(shades.length-1, max(intensity, 0));

intensity = min(shades.length - 1, max(intensity, 0));

~~putchar(~~shades[intensity]);

shades[intensity].putchar;

} else

~~putchar(~~' ');

' '.putchar;

}

~~putchar(~~'\n');

'\n'.putchar;

}

void main() {

light.normalize();

drawSphere(20, 4, 0.1);

drawSphere(10, 2, 0.4);