CG[LWJGL0019] || Color

Table of contents

Bagi anda yang sering menggunakan library Color dengan cara import java.awt.Color; maupun import android.graphics.Color; maka anda akan merasa sedikit ganjil ketika menggunakan encode color dalam LWJGL/OpenGL karena dalam OpenGL warna RGBA di encode dalam tipe data float sedangkan dalam pure java kita lebih sering menggunakan format integer (interval 0 sampai 255). Sebenarnya dalam pure java juga sudah disediakan Color tipe float yang kita kenal dengan tipe HSB tetapi kita juga dapat membuat custom Class Color kita sendiri seperti contoh berikut ini dan kita dapat memanggilnya sewaktu-waktu diperlukan:

	public class Color {
	/** The fixed color transparent */
	public static final Color TRANSPARENT = new Color(0.0f, 0.0f, 0.0f, 0.0f);
	/** The fixed colour white */
	public static final Color WHITE = new Color(1.0f, 1.0f, 1.0f, 1.0f);
	/** The fixed colour yellow */
	public static final Color YELLOW = new Color(1.0f, 1.0f, 0, 1.0f);
	/** The fixed colour red */
	public static final Color RED = new Color(1.0f, 0, 0, 1.0f);
	/** The fixed colour blue */
	public static final Color BLUE = new Color(0, 0, 1.0f, 1.0f);
	/** The fixed colour green */
	public static final Color GREEN = new Color(0, 1.0f, 0, 1.0f);
	/** The fixed colour black */
	public static final Color BLACK = new Color(0, 0, 0, 1.0f);
	/** The fixed colour gray */
	public static final Color GRAY = new Color(0.5f, 0.5f, 0.5f, 1.0f);
	/** The fixed colour cyan */
	public static final Color CYAN = new Color(0, 1.0f, 1.0f, 1.0f);
	/** The fixed colour dark gray */
	public static final Color DARK_GRAY = new Color(0.3f, 0.3f, 0.3f, 1.0f);
	/** The fixed colour light gray */
	public static final Color LIGHT_GRAY = new Color(0.7f, 0.7f, 0.7f, 1.0f);
	/** The fixed colour dark pink */
	public final static Color PINK = new Color(255, 175, 175, 255);
	/** The fixed colour dark orange */
	public final static Color ORANYE = new Color(255, 200, 0, 255);
	/** The fixed colour dark magenta */
	public final static Color MAGENTA = new Color(255, 0, 255, 255);
	/** The fixed color from http://flatuicolors.com/ */
	public final static Color TURQUOISE =new Color(26, 188, 156);
	public final static Color EMERALD =new Color(46, 204, 113);
	public final static Color PETER_RIVER = new Color(52, 152, 219);
	public final static Color AMETHYST = new Color(155, 89, 182);
	public final static Color WET_ASPHALT = new Color(52, 73, 94);
	public final static Color GREEN_SEA = new Color(22, 160, 133);
	public final static Color NEPHRITIS = new Color(39, 174, 96);
	public final static Color BELIZE_HOLE = new Color(41, 128, 185);
	public final static Color WISTERIA = new Color(142, 68, 173);
	public final static Color MIDNIGHT_BLUE = new Color(44, 62, 80);
	public final static Color SUN_FLOWER = new Color(241, 196, 15);
	public final static Color CARROT = new Color(230, 126, 34);
	public final static Color ALIZARIN = new Color(231, 76, 60);
	public final static Color CLOUDS = new Color(236, 240, 241);
	public final static Color CONCRETE = new Color(149, 165, 166);
	public final static Color ORANGE = new Color(243, 156, 18);
	public final static Color PUMPKIN = new Color(211, 84, 0);
	public final static Color POMEGRANATE = new Color(192, 57, 43);
	public final static Color SILVER = new Color(189, 195, 199);
	public final static Color ASBESTOS = new Color(127, 140, 141);
	/** The red component [0.0 - 1.0]. */
	public float r;
	/** The green component [0.0 - 1.0]. */
	public float g;
	/** The blue component [0.0 - 1.0]. */
	public float b;
	/** The alpha component [0.0 - 1.0]. */
	public float a;
	/** Create a 4 component colour
	*
	* @param r The red component of the colour (0.0 -> 1.0)
	* @param g The green component of the colour (0.0 -> 1.0)
	* @param b The blue component of the colour (0.0 -> 1.0)
	* @param a The alpha component of the colour (0.0 -> 1.0) */
	public Color(float r, float g, float b, float a) {
	this.r = r;
	this.g = g;
	this.b = b;
	this.a = a;
	}
	/** Create a 3 component colour; alpha is passed as 1.0 (255).
	*
	* @param r The red component of the colour (0.0 -> 1.0)
	* @param g The green component of the colour (0.0 -> 1.0)
	* @param b The blue component of the colour (0.0 -> 1.0) */
	public Color(float r, float g, float b) {
	this(r, g, b, 1f);
	}
	/** Create a 4 component colour
	*
	* @param r The red component of the colour (0 -> 255)
	* @param g The green component of the colour (0 -> 255)
	* @param b The blue component of the colour (0 -> 255)
	* @param a The alpha component of the colour (0 -> 255) */
	public Color(int r, int g, int b, int a) {
	this(r / 255f, g / 255f, b / 255f, a / 255f);
	}
	/** Create a 3 component colour; alpha is passed as 255 (1.0).
	*
	* @param r The red component of the colour (0 -> 255)
	* @param g The green component of the colour (0 -> 255)
	* @param b The blue component of the colour (0 -> 255) */
	public Color(int r, int g, int b) {
	this(r, g, b, 255);
	}
	/** Creates a WHITE color. */
	public Color() {
	this(Color.WHITE);
	}
	/** Copy constructor
	*
	* @param color The color to copy into the new instance */
	public Color(Color color) {
	this(color.r, color.g, color.b, color.a);
	}
	/** Create a colour from an integer packed 0xAARRGGBB. If AA is specified as
	* zero then it will be interpreted as unspecified and hence a value of 255
	* will be recorded.
	*
	* @param value The value to interpret for the colour */
	public Color(int value) {
	int r = (value & 0x00FF0000) >> 16;
	int g = (value & 0x0000FF00) >> 8;
	int b = (value & 0x000000FF);
	int a = (value & 0xFF000000) >> 24;
	if (a < 0)
	a += 256;
	if (a == 0)
	a = 255;
	this.r = r / 255.0f;
	this.g = g / 255.0f;
	this.b = b / 255.0f;
	this.a = a / 255.0f;
	}
	/** Decode a number in a string and process it as a colour.
	*
	* @param nm The number string to decode
	* @return The color created from the number read
	* @throws NumberFormatException if the string was invalid */
	public static Color decode(String nm) {
	return new Color(Integer.decode(nm).intValue());
	}
	/** Get the red byte component of this colour
	*
	* @return The red component (range 0-255) */
	public int red() {
	return (int) (r * 255);
	}
	/** Get the green byte component of this colour
	*
	* @return The green component (range 0-255) */
	public int green() {
	return (int) (g * 255);
	}
	/** Get the blue byte component of this colour
	*
	* @return The blue component (range 0-255) */
	public int blue() {
	return (int) (b * 255);
	}
	/** Get the alpha byte component of this colour
	*
	* @return The alpha component (range 0-255) */
	public int alpha() {
	return (int) (a * 255);
	}
	public void set(Color color) {
	set(color.r, color.g, color.b, color.a);
	}
	public void set(float r, float g, float b, float a) {
	set(r, g, b);
	this.a = a;
	}
	public void set(float r, float g, float b) {
	this.r = r;
	this.g = g;
	this.b = b;
	}
	/** Packs the 4 components of this color into a 32-bit int.
	*
	* @return the packed color as a 32-bit int. */
	public int toIntBits() {
	int color = ((int) (255 * a) << 24) | ((int) (255 * b) << 16) | ((int) (255 * g) << 8)
	| ((int) (255 * r));
	return color;
	}
	/** @see java.lang.Object#hashCode() */
	public int hashCode() {
	return ((int) (r + g + b + a) * 255);
	}
	/** @see java.lang.Object#equals(java.lang.Object) */
	public boolean equals(Object other) {
	if (other instanceof Color) {
	Color o = (Color) other;
	return ((o.r == r) && (o.g == g) && (o.b == b) && (o.a == a));
	}
	return false;
	}
	/** @see java.lang.Object#toString() */
	public String toString() {
	return "Color (" + r + "," + g + "," + b + "," + a + ")";
	}
	}

view raw Color.java hosted with ❤ by GitHub

Perhatikan method:

public Color(int r, int g, int b, int a) {


this(r / 255f, g / 255f, b / 255f, a / 255f); 

 }

method ini berguna untuk mengembalikan range nilai rgba ke interval 0 - 255.
dengan code class Color ini kita bisa merasakan pure java color coding di OpenGL :) :) :) :) :)
sebagai tambahan class Color ini juga menyertakan warna-warna dari http://flatuicolors.com/.

lihat semua tutorial

Referensi:
- https://github.com/mattdesl/lwjgl-basics/blob/master/src/mdesl/graphics/Color.java