gov.nasa.worldwind.util
Class OGLUtil

java.lang.Object
  gov.nasa.worldwind.util.OGLUtil

public class OGLUtil
extends Object

A collection of OpenGL utility methods, all static.

Field Summary

static int	DEFAULT_COMBINE_ALPHA
static int	DEFAULT_COMBINE_RGB
protected static Vec4	DEFAULT_LIGHT_DIRECTION
static int	DEFAULT_SRC0_ALPHA
static int	DEFAULT_SRC0_RGB
static int	DEFAULT_SRC1_ALPHA
static int	DEFAULT_SRC1_RGB
static int	DEFAULT_SRC2_ALPHA
static int	DEFAULT_SRC2_RGB
static int	DEFAULT_TEX_ENV_MODE
static int	DEFAULT_TEXTURE_GEN_MODE
static double[]	DEFAULT_TEXTURE_GEN_S_OBJECT_PLANE
static double[]	DEFAULT_TEXTURE_GEN_T_OBJECT_PLANE
protected static String	GL_EXT_BLEND_FUNC_SEPARATE

Constructor Summary

OGLUtil()

Method Summary

static void	applyBlending(GL2 gl, boolean havePremultipliedColors) Sets the GL blending state according to the specified color mode.
static void	applyColor(GL2 gl, Color color, boolean premultiplyColors) Sets the GL color state to the specified Color, and with the specified color mode.
static void	applyColor(GL2 gl, Color color, double opacity, boolean premultiplyColors) Sets the GL color state to the specified Color and opacity, and with the specified color mode.
static void	applyLightingDirectionalFromViewer(GL2 gl, int light, Vec4 direction) Sets the GL lighting state to a white light originating from the eye position and pointed in the specified direction, in model coordinates.
static int	computeTexturePixelFormat(int internalFormat) Returns an OpenGL pixel format corresponding to the specified texture internal format.
static int	estimateTextureMemorySize(int internalFormat, int width, int height, boolean includeMipmaps) Returns an OpenGL pixel format corresponding to the specified texture internal format.
static TextureData	newTextureData(GLProfile glp, File file, boolean useMipMaps) Creates TextureData from a File.
static TextureData	newTextureData(GLProfile glp, InputStream stream, boolean useMipMaps) Creates TextureData from an InputStream.
static TextureData	newTextureData(GLProfile glp, URL url, boolean useMipMaps) Creates TextureData from the given URL.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_COMBINE_ALPHA

public static final int DEFAULT_COMBINE_ALPHA

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Constant Field Values

DEFAULT_COMBINE_RGB

public static final int DEFAULT_COMBINE_RGB

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Constant Field Values

DEFAULT_LIGHT_DIRECTION

protected static final Vec4 DEFAULT_LIGHT_DIRECTION

DEFAULT_SRC0_ALPHA

public static final int DEFAULT_SRC0_ALPHA

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Constant Field Values

DEFAULT_SRC0_RGB

public static final int DEFAULT_SRC0_RGB

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Constant Field Values

DEFAULT_SRC1_ALPHA

public static final int DEFAULT_SRC1_ALPHA

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Constant Field Values

DEFAULT_SRC1_RGB

public static final int DEFAULT_SRC1_RGB

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Constant Field Values

DEFAULT_SRC2_ALPHA

public static final int DEFAULT_SRC2_ALPHA

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Constant Field Values

DEFAULT_SRC2_RGB

public static final int DEFAULT_SRC2_RGB

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Constant Field Values

DEFAULT_TEX_ENV_MODE

public static final int DEFAULT_TEX_ENV_MODE

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Constant Field Values

DEFAULT_TEXTURE_GEN_MODE

public static final int DEFAULT_TEXTURE_GEN_MODE

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Constant Field Values

DEFAULT_TEXTURE_GEN_S_OBJECT_PLANE

public static final double[] DEFAULT_TEXTURE_GEN_S_OBJECT_PLANE

DEFAULT_TEXTURE_GEN_T_OBJECT_PLANE

public static final double[] DEFAULT_TEXTURE_GEN_T_OBJECT_PLANE

GL_EXT_BLEND_FUNC_SEPARATE

protected static final String GL_EXT_BLEND_FUNC_SEPARATE

See Also:

Constant Field Values

Constructor Detail

OGLUtil

public OGLUtil()

Method Detail

applyBlending

public static void applyBlending(GL2 gl,
                                 boolean havePremultipliedColors)

Sets the GL blending state according to the specified color mode. If havePremultipliedColors is true, this applies a blending function appropriate for colors premultiplied by the alpha component. Otherwise, this applies a blending function appropriate for non-premultiplied colors.

Parameters:

gl - the GL context.

havePremultipliedColors - true to configure blending for colors premultiplied by the alpha components, and false to configure blending for non-premultiplied colors.

Throws:

IllegalArgumentException - if the GL is null.

applyColor

public static void applyColor(GL2 gl,
                              Color color,
                              boolean premultiplyColors)

Sets the GL color state to the specified Color, and with the specified color mode. If premultiplyColors is true, this premultipies the Red, Green, and Blue color values by the Alpha value. Otherwise, this does not modify the Red, Green, and Blue color values.

Parameters:

gl - the GL context.

color - the Red, Green, Blue, and Alpha values to set.

premultiplyColors - true to premultiply the Red, Green and Blue color values by the Alpha value, false to leave the Red, Green, and Blue values unmodified.

Throws:

IllegalArgumentException - if the GL is null, if the Color is null, if the opacity is less than 0, or if the opacity is greater than 1.

applyColor

public static void applyColor(GL2 gl,
                              Color color,
                              double opacity,
                              boolean premultiplyColors)

Sets the GL color state to the specified Color and opacity, and with the specified color mode. If premultiplyColors is true, this premultipies the Red, Green, and Blue color values by the opacity value. Otherwise, this does not modify the Red, Green, and Blue color values.

Parameters:

gl - the GL context.

color - the Red, Green, and Blue values to set.

opacity - the opacity to set.

premultiplyColors - true to premultiply the Red, Green, and Blue color values by the opacity value, false to leave the Red, Green, and Blue values unmodified.

Throws:

IllegalArgumentException - if the GL is null, if the Color is null, if the opacity is less than 0, or if the opacity is greater than 1.

applyLightingDirectionalFromViewer

public static void applyLightingDirectionalFromViewer(GL2 gl,
                                                      int light,
                                                      Vec4 direction)

Sets the GL lighting state to a white light originating from the eye position and pointed in the specified direction, in model coordinates. The light direction is always relative to the current eye point and viewer direction. If the direction is null, this the light direction defaults to (0, 0, -1), which points directly along the forward vector form the eye point

Parameters:

gl - the GL context.

light - the GL light name to set.

direction - the light direction in model coordinates, may be null.

Throws:

IllegalArgumentException - if the GL is null.

computeTexturePixelFormat

public static int computeTexturePixelFormat(int internalFormat)

Returns an OpenGL pixel format corresponding to the specified texture internal format. This maps internal format to pixel format as follows:

This returns 0 if the internal format is not one of the recognized types.

Parameters:

internalFormat - the OpenGL texture internal format.

Returns:

a pixel format corresponding to the texture internal format, or 0 if the internal format is not recognized.

estimateTextureMemorySize

public static int estimateTextureMemorySize(int internalFormat,
                                            int width,
                                            int height,
                                            boolean includeMipmaps)

Returns an OpenGL pixel format corresponding to the specified texture internal format. This maps internal format to pixel format as follows:

Internal Format	Pixel Format
GL2.GL_ALPHA	GL2.GL_ALPHA
GL2.GL_ALPHA4	GL2.GL_ALPHA
GL2.GL_ALPHA8	GL2.GL_ALPHA
GL2.GL_ALPHA12	GL2.GL_ALPHA
GL2.GL_ALPHA16	GL2.GL_ALPHA
GL2.GL_COMPRESSED_ALPHA	GL2.GL_ALPHA
GL2.GL_COMPRESSED_LUMINANCE	GL2.GL_LUMINANCE
GL2.GL_COMPRESSED_LUMINANCE_ALPHA	GL2.GL_LUMINANCE_ALPHA
GL2.GL_COMPRESSED_INTENSITY	GL2.GL_RED
GL2.GL_COMPRESSED_RGB	GL2.GL_RGB
GL2.GL_COMPRESSED_RGBA	GL2.GL_RGBA
GL2.GL_DEPTH_COMPONENT	GL2.GL_RED
GL2.GL_DEPTH_COMPONENT16	GL2.GL_RED
GL2.GL_DEPTH_COMPONENT24	GL2.GL_RED
GL2.GL_DEPTH_COMPONENT32	GL2.GL_RED
GL2.GL_LUMINANCE	GL2.GL_LUMINANCE
GL2.GL_LUMINANCE4	GL2.GL_LUMINANCE
GL2.GL_LUMINANCE8	GL2.GL_LUMINANCE
GL2.GL_LUMINANCE12	GL2.GL_LUMINANCE
GL2.GL_LUMINANCE16	GL2.GL_LUMINANCE
GL2.GL_LUMINANCE_ALPHA	GL2.GL_LUMINANCE_ALPHA
GL2.GL_LUMINANCE4_ALPHA4	GL2.GL_LUMINANCE_ALPHA
GL2.GL_LUMINANCE6_ALPHA2	GL2.GL_LUMINANCE_ALPHA
GL2.GL_LUMINANCE8_ALPHA8	GL2.GL_LUMINANCE_ALPHA
GL2.GL_LUMINANCE12_ALPHA4	GL2.GL_LUMINANCE_ALPHA
GL2.GL_LUMINANCE12_ALPHA12	GL2.GL_LUMINANCE_ALPHA
GL2.GL_LUMINANCE16_ALPHA16	GL2.GL_LUMINANCE_ALPHA
GL2.GL_INTENSITY	GL2.GL_RED
GL2.GL_INTENSITY4	GL2.GL_RED
GL2.GL_INTENSITY8	GL2.GL_RED
GL2.GL_INTENSITY12	GL2.GL_RED
GL2.GL_INTENSITY16	GL2.GL_RED
GL2.GL_R3_G3_B2	GL2.GL_RGB
GL2.GL_RGB	GL2.GL_RGB
GL2.GL_RGB4	GL2.GL_RGB
GL2.GL_RGB5	GL2.GL_RGB
GL2.GL_RGB8	GL2.GL_RGB
GL2.GL_RGB10	GL2.GL_RGB
GL2.GL_RGB12	GL2.GL_RGB
GL2.GL_RGB16	GL2.GL_RGB
GL2.GL_RGBA	GL2.GL_RGBA
GL2.GL_RGBA2	GL2.GL_RGBA
GL2.GL_RGBA4	GL2.GL_RGBA
GL2.GL_RGB5_A1	GL2.GL_RGBA
GL2.GL_RGBA8	GL2.GL_RGBA
GL2.GL_RGB10_A2	GL2.GL_RGBA
GL2.GL_RGBA12	GL2.GL_RGBA
GL2.GL_RGBA16	GL2.GL_RGBA
GL2.GL_SLUMINANCE	GL2.GL_LUMINANCE
GL2.GL_SLUMINANCE8	GL2.GL_LUMINANCE
GL2.GL_SLUMINANCE_ALPHA	GL2.GL_LUMINANCE_ALPHA
GL2.GL_SLUMINANCE8_ALPHA8	GL2.GL_LUMINANCE_ALPHA
GL2.GL_SRGB	GL2.GL_RGB
GL2.GL_SRGB8	GL2.GL_RGB
GL2.GL_SRGB_ALPHA	GL2.GL_RGBA
GL2.GL_SRGB8_ALPHA8	GL2.GL_RGBA

The returned estimate assumes that the driver provides does not convert the formats to another supported, such converting as GL2.GL_ALPHA4 to GL2.GL_ALPHA8. This returns 0 if the internal format is not one of the recognized types. This does not attempt to estimate a memory size for compressed internal formats.

Parameters:

internalFormat - the OpenGL texture internal format.

width - the texture width, in pixels.

height - the texture height, in pixels.

includeMipmaps - true to include the texture's mip map data in the estimated size; false otherwise.

Returns:

a pixel format corresponding to the texture internal format, or 0 if the internal format is not recognized.

Throws:

IllegalArgumentException - if either the width or height is less than or equal to zero.

newTextureData

public static TextureData newTextureData(GLProfile glp,
                                         File file,
                                         boolean useMipMaps)
                                  throws IOException

Creates TextureData from a File. Does no OpenGL work.

Parameters:

glp - the OpenGL Profile this texture data should be created for.

file - the file from which to read the texture data

useMipMaps - whether mipmaps should be produced for this texture either by auto-generating them or reading them from the file. Some file formats support multiple mipmaps in a single file in which case those mipmaps will be used rather than generating them.

Returns:

the texture data from the URL, or null if none of the registered texture providers could read the URL

Throws:

IOException - if an error occurred while reading the URL

newTextureData

public static TextureData newTextureData(GLProfile glp,
                                         InputStream stream,
                                         boolean useMipMaps)
                                  throws IOException

Creates TextureData from an InputStream. Does no OpenGL work.

Parameters:

glp - the OpenGL Profile this texture data should be created for.

stream - the stream from which to read the texture data

useMipMaps - whether mipmaps should be produced for this texture either by auto-generating them or reading them from the file. Some file formats support multiple mipmaps in a single file in which case those mipmaps will be used rather than generating them.

Returns:

the texture data from the URL, or null if none of the registered texture providers could read the URL

Throws:

IOException - if an error occurred while reading the URL

newTextureData

public static TextureData newTextureData(GLProfile glp,
                                         URL url,
                                         boolean useMipMaps)
                                  throws IOException

Creates TextureData from the given URL. Does no OpenGL work.

Parameters:

glp - the OpenGL Profile this texture data should be created for.

url - the URL from which to read the texture data

useMipMaps - whether mipmaps should be produced for this texture either by auto-generating them or reading them from the file. Some file formats support multiple mipmaps in a single file in which case those mipmaps will be used rather than generating them.

Returns:

the texture data from the URL, or null if none of the registered texture providers could read the URL

Throws:

IOException - if an error occurred while reading the URL