Description

A data structure giving you full control over grass properties.

Grass is added to the scene through GrassLoader::addLayer(). Through this class you can configure your grass layer any way you like - size, density, render technique, animation, etc. Simply call the appropriate "set" member function to set the desired property.

Remember that you cannot create or delete layers directly. Layers can only be created with GrassLoader::addLayer(), and may not be deleted manually (they will be deleted when the associated GrassLoader is deleted).

Definition at line 228 of file GrassLoader.h.

Public Member Functions
void	setMaterialName (const Ogre::String &matName)

void	setMinimumSize (float width, float height)

void	setMaximumSize (float width, float height)

void	setDensity (float density)

void	setHeightRange (float minHeight, float maxHeight=0)

void	setMaxSlope (const float maxSlopeRatio)

void	setMaxSlope (Ogre::Radian maxSlopeAngle)

Ogre::Real	getMaxSlope () const

void	setDensityMap (const Ogre::String &mapFile, MapChannel channel=CHANNEL_COLOR)

void	setDensityMap (Ogre::TexturePtr map, MapChannel channel=CHANNEL_COLOR)

void	setDensityMapFilter (MapFilter filter)

void	setColorMap (const Ogre::String &mapFile, MapChannel channel=CHANNEL_COLOR)

void	setColorMap (Ogre::TexturePtr map, MapChannel channel=CHANNEL_COLOR)

void	setColorMapFilter (MapFilter filter)

void	setMapBounds (const TBounds &bounds)

DensityMap *	getDensityMap () const

ColorMap *	getColorMap () const

bool	getBlendValue () const

GrassLoader *	getParentGrassLoader () const

bool	getLightingEnabled () const

const TBounds &	getMapBounds () const

void	setRenderTechnique (GrassTechnique style, bool blendBase=false)

void	setFadeTechnique (FadeTechnique style)

void	setAnimationEnabled (bool enabled)

void	setLightingEnabled (bool enabled)

void	setSwayLength (Ogre::Real mag)

void	setSwaySpeed (Ogre::Real speed)

void	setSwayDistribution (Ogre::Real freq)

Private Member Functions
	GrassLayer (PagedGeometry geom, GrassLoader ldr)

	~GrassLayer ()

void	_updateShaders ()

unsigned int	_populateGrassList_Uniform (PageInfo page, float *posBuff, unsigned int grassCount)

unsigned int	_populateGrassList_UnfilteredDM (PageInfo page, float *posBuff, unsigned int grassCount)

unsigned int	_populateGrassList_BilinearDM (PageInfo page, float *posBuff, unsigned int grassCount)

Private Attributes
GrassLoader *	parent

Ogre::MaterialPtr	material

Ogre::Real	density

Ogre::Real	minWidth

Ogre::Real	maxWidth

Ogre::Real	minHeight

Ogre::Real	maxHeight

Ogre::Real	minY

Ogre::Real	maxY

Ogre::Real	maxSlope

FadeTechnique	fadeTechnique

GrassTechnique	renderTechnique

TBounds	mapBounds

DensityMap *	densityMap

MapFilter	densityMapFilter

ColorMap *	colorMap

MapFilter	colorMapFilter

bool	animate

bool	blend

bool	lighting

bool	shaderNeedsUpdate

Ogre::Real	animMag

Ogre::Real	animSpeed

Ogre::Real	animFreq

Ogre::Real	waveCount

PagedGeometry *	geom

Friends
class	GrassLoader

Constructor & Destructor Documentation

◆ GrassLayer()

Forests::GrassLayer::GrassLayer	(	PagedGeometry *	geom,
		GrassLoader *	ldr
	)

private

Do not create a GrassLayer directly - use GrassLoader->addLayer()

Definition at line 724 of file GrassLoader.cpp.

◆ ~GrassLayer()

Forests::GrassLayer::~GrassLayer ( )

private

Do not delete a GrassLayer yourself - the GrassLoader will do this automatically when it's deleted.

Definition at line 751 of file GrassLoader.cpp.

Member Function Documentation

◆ _populateGrassList_BilinearDM()

unsigned int Forests::GrassLayer::_populateGrassList_BilinearDM	(	PageInfo	page,
		float *	posBuff,
		unsigned int	grassCount
	)

private

Definition at line 987 of file GrassLoader.cpp.

◆ _populateGrassList_UnfilteredDM()

unsigned int Forests::GrassLayer::_populateGrassList_UnfilteredDM	(	PageInfo	page,
		float *	posBuff,
		unsigned int	grassCount
	)

private

Definition at line 914 of file GrassLoader.cpp.

◆ _populateGrassList_Uniform()

unsigned int Forests::GrassLayer::_populateGrassList_Uniform	(	PageInfo	page,
		float *	posBuff,
		unsigned int	grassCount
	)

private

Definition at line 846 of file GrassLoader.cpp.

◆ _updateShaders()

void Forests::GrassLayer::_updateShaders ( )

private

Definition at line 1090 of file GrassLoader.cpp.

◆ getBlendValue()

bool Forests::GrassLayer::getBlendValue ( ) const

inline

Gives back the value of blending.

Definition at line 412 of file GrassLoader.h.

◆ getColorMap()

ColorMap * Forests::GrassLayer::getColorMap ( ) const

inline

Gets a pointer to the color map being used.

You can use this function to access the internal color map object used by the GrassLoader. Through this object you can directly manipulate the pixels of the color map, among other things.

Note that although you can edit the color map in real-time through this class, the changes won't be uploaded to your video card until you call PagedGeometry::reloadGeometry(). If you don't, the grass you see will remain unchanged.

Definition at line 409 of file GrassLoader.h.

◆ getDensityMap()

DensityMap * Forests::GrassLayer::getDensityMap ( ) const

inline

Gets a pointer to the density map being used.

You can use this function to access the internal density map object used by the GrassLoader. Through this object you can directly manipulate the pixels of the density map, among other things.

Note that although you can edit the density map in real-time through this class, the changes won't be uploaded to your video card until you call PagedGeometry::reloadGeometry(). If you don't, the grass you see will remain unchanged.

Definition at line 398 of file GrassLoader.h.

◆ getLightingEnabled()

bool Forests::GrassLayer::getLightingEnabled ( ) const

inline

Gives back if lighting is enabled for grass.

Definition at line 418 of file GrassLoader.h.

◆ getMapBounds()

const TBounds & Forests::GrassLayer::getMapBounds ( ) const

inline

Gets the map bounds.

Definition at line 421 of file GrassLoader.h.

◆ getMaxSlope()

Ogre::Real Forests::GrassLayer::getMaxSlope ( ) const

inline

Get the maximum slope a grass blade can be placed on (as set by setMaxSlope()).

Returns: The currently set maximum slope ratio value (not an angle).

This returns the currently set maximum slope which is used to determine what ground is too steep for grass to be placed on. Note that this returns the slope as a slope ratio, not an angle. If you need an angle value, convert with ATan() (maxSlopeAngle = ATan(maxSlopeRatio)).

Definition at line 286 of file GrassLoader.h.

◆ getParentGrassLoader()

GrassLoader * Forests::GrassLayer::getParentGrassLoader ( ) const

inline

Gets the parent grassLoader of this layer.

Definition at line 415 of file GrassLoader.h.

◆ setAnimationEnabled()

void Forests::GrassLayer::setAnimationEnabled ( bool enabled )

Enables/disables animation on this layer.

Always use this function to disable animation, rather than setting SwayLength or SwaySpeed to 0. This function will use a different vertex shader which means improved performance when animation is disabled.

Definition at line 803 of file GrassLoader.cpp.

◆ setColorMap() [1/2]

void Forests::GrassLayer::setColorMap	(	const Ogre::String &	mapFile,
		MapChannel	channel = `CHANNEL_COLOR`
	)

Sets the color map used for this grass layer.

Parameters

mapFile	The color map image
channel	The color channel(s) to from the image to use

A color map is simply a texture that allows you to vary the color and shading of grass across your world for a more realistic look. For example, adding a dark spot to the center of your color map will make grass near the center of your terrain look darker, as long as you have the color map aligned to your terrain (see setMapBounds()).

The channel parameter allows you to extract the color information from the image's red, green, blue, alpha, or color values. For example, you may store the desired shade of your grass in the red channel of an image, in which case you would use CHANNEL_RED (when you choose a single channel, it is converted to a greyscale color). By default, CHANNEL_COLOR is used, which uses the full color information available in the image.

Remember that GrassLayer by default has no idea of your terrain/world boundaries, so you must specify a rectangular/square area of your world that is affected by density/color maps. To do this, use the setMapBounds() function. Normally this is set to your terrain's bounds so the density/color map is aligned to your heightmap, but you could apply it anywhere you want.

◆ setColorMap() [2/2]

void Forests::GrassLayer::setColorMap	(	Ogre::TexturePtr	map,
		MapChannel	channel = `CHANNEL_COLOR`
	)

Sets the color map used for this grass layer.

Overloaded to accept a Texture object. See the original setColorMap() documentation above for more detailed information on color maps.

Note: The texture data you provide is copied into RAM, so you can delete the texture after calling this function without risk of crashing.

◆ setColorMapFilter()

void Forests::GrassLayer::setColorMapFilter ( MapFilter filter )

Sets the filtering mode used for color maps.

This function can be used to set the filtering mode used for your color map when generating grass. By default, bilinear filtering is used (MAPFILTER_BILINEAR). If you disable filtering by using MAPFILTER_NONE, the resulting grass coloration may appear slightly pixelated, depending on the resolution of your color map.

MAPFILTER_NONE is slightly faster than MAPFILTER_BILINEAR, so use it if you don't notice any considerable pixelation.

Definition at line 1083 of file GrassLoader.cpp.

◆ setDensity()

void Forests::GrassLayer::setDensity ( float density )

inline

Sets the maximum density (measured in grass quads/billboards per square unit) of grass.

Definition at line 241 of file GrassLoader.h.

◆ setDensityMap() [1/2]

void Forests::GrassLayer::setDensityMap	(	const Ogre::String &	mapFile,
		MapChannel	channel = `CHANNEL_COLOR`
	)

Sets the density map used for this grass layer.

Parameters

mapFile	The density map image
channel	The color channel(s) to from the image to interpret as density

A density map is simply a greyscale image, similar to a heightmap, that specifies the grass density on your map. Full pixel intensity indicates that grass should be fully dense at that point (the maximum density is specified by GrassLayer::setDensity()), while no pixel intensity indicates that no grass should appear at that location.

The channel parameter allows you to extract the density information from the image's red, green, blue, alpha, or color values. For example, you may store density values in the alpha channel, in which case you would use CHANNEL_ALPHA. By default, CHANNEL_COLOR is used, which means the image color is converted to greyscale internally and used as a density map.

Note that GrassLayer by default has no idea of your terrain/world boundaries, so you must specify a rectangular/square area of your world that is affected by density/color maps. To do this, use the setMapBounds() function. Normally this is set to your terrain's bounds so the density/color map is aligned to your heightmap, but you could apply it anywhere you want.

◆ setDensityMap() [2/2]

void Forests::GrassLayer::setDensityMap	(	Ogre::TexturePtr	map,
		MapChannel	channel = `CHANNEL_COLOR`
	)

Sets the density map used for this grass layer.

Overloaded to accept a Texture object. See the original setDensityMap() documentation above for more detailed information on density maps.

Note: The texture data you provide is copied into the GrassLayer's own memory space, so you can delete the texture after calling this function without risk of crashing.

◆ setDensityMapFilter()

void Forests::GrassLayer::setDensityMapFilter ( MapFilter filter )

Sets the filtering mode used for density maps.

This function can be used to set the filtering mode used for your density map when generating grass. By default, bilinear filtering is used (MAPFILTER_BILINEAR). If you disable filtering by using MAPFILTER_NONE, the resulting layout of your grass may look square and blocky, depending on the resolution of your density map.

MAPFILTER_NONE is slightly faster than MAPFILTER_BILINEAR, so use it if you don't notice any considerable blockiness.

Definition at line 839 of file GrassLoader.cpp.

◆ setFadeTechnique()

void Forests::GrassLayer::setFadeTechnique ( FadeTechnique style )

Sets the technique used when fading out distant grass.

Parameters

style The FadeTechnique style used to fade grass.

This "style" setting allows you to choose from various fade techniques. Depending on your scene, certain techniques may look better than others. The most compatible method is FADETECH_ALPHA (used by default), although better results can usually be achieved with other methods. See the FadeTechnique documentation for more information.

Definition at line 795 of file GrassLoader.cpp.

◆ setHeightRange()

void Forests::GrassLayer::setHeightRange	(	float	minHeight,
		float	maxHeight = `0`
	)

inline

Sets a minimum / maximum height where grass may appear.

Parameters

minHeight	Sets the minimum height grass may have. 0 = no minimum
maxHeight	Sets the maximum height grass may have. 0 = no maximum

By default grass appears at all altitudes. You can use this function to restrict grass to a certain height range. For example, if sea level is at 100 units Y, you might restrict this layer to display only above 100 units (so your grass doesn't grow under water).

It's possible to use density maps (see setDensityMap()) to achieve similar results, but if your density map is extremely low resolution, this function may be the only practical option to prevent grass from growing under water (when used in combination with your density map).

Setting minHeight to 0 means grass has no minimum height - it can grow as low as necessary. Similarly, setting maxHeight to 0 means grass has no maximum height - it can grow as high as necessary.

Definition at line 258 of file GrassLoader.h.

◆ setLightingEnabled()

void Forests::GrassLayer::setLightingEnabled ( bool enabled )

Enables/disables lighting on this layer.

Definition at line 811 of file GrassLoader.cpp.

◆ setMapBounds()

void Forests::GrassLayer::setMapBounds ( const TBounds & bounds )

inline

Sets the boundaries of the density/color maps.

Parameters

bounds The map boundary

By default, the GrassLayer has no knowledge of your terrain/world boundaries, so you must use this function to specify a rectangular/square area of your world, otherwise density/color maps won't work properly. The boundary given to this function defines the area where density/color maps take effect. Normally this is set to your terrain's bounds so the density/color map is aligned to your heightmap, but you could apply it anywhere you want.

Note: The grass system is infinite, so there's no need to worry about using too expansive boundaries. This setting simply configures the behavior of density and color maps.

Definition at line 384 of file GrassLoader.h.

◆ setMaterialName()

void Forests::GrassLayer::setMaterialName ( const Ogre::String & matName )

Sets the material that is applied to all grass billboards/quads.

Definition at line 759 of file GrassLoader.cpp.

◆ setMaximumSize()

void Forests::GrassLayer::setMaximumSize	(	float	width,
		float	height
	)

Sets the maximum size that grass quads/billboards will be.

Definition at line 775 of file GrassLoader.cpp.

◆ setMaxSlope() [1/2]

void Forests::GrassLayer::setMaxSlope ( const float maxSlopeRatio )

inline

Set the maximum slope a grass of blade can be placed on.

Parameters

maxSlopeRatio The maximum slope (h/w ratio) a grass blade is allowed to be placed on.

This function can be used to set the maximum slope you want your grass to be placed on (although it doesn't work for sprite grass). By default grass is allowed on any slope.

This version of setMaxSlope() accepts a slope ratio value, where ATan(maxSlopeRatio) = maxSlopeAngle. If you wish to provide a maximum slope as an angle, either use the other overload of this function, or convert your angle to a slope ratio first with Tan().

Definition at line 269 of file GrassLoader.h.

◆ setMaxSlope() [2/2]

void Forests::GrassLayer::setMaxSlope ( Ogre::Radian maxSlopeAngle )

inline

Definition at line 271 of file GrassLoader.h.

◆ setMinimumSize()

void Forests::GrassLayer::setMinimumSize	(	float	width,
		float	height
	)

Sets the minimum size that grass quads/billboards will be.

Definition at line 769 of file GrassLoader.cpp.

◆ setRenderTechnique()

void Forests::GrassLayer::setRenderTechnique	(	GrassTechnique	style,
		bool	blendBase = `false`
	)

Sets the technique used to render this grass layer.

Parameters

style	The GrassTechnique style used to display grass.
blendBase	Whether or not grass base blending is enabled.

The "style" setting allows you to choose from various construction methods, such as sprite-style grass quads, plain 3D quads, etc. See the GrassTechnique documentation for more information about this option. GRASSTECH_QUAD is used by default.

Setting "blendBase" to true will enable grass base blending, a technique which helps reduce the unnatural flat appearance of grass quads near the camera. Since the flatness is most obvious where the grass intersects the terrain, this technique attempts to smoothly blend the base of near-by grass into the terrain.

Note: Base blending does not work well with alpha-rejected textures.

Definition at line 784 of file GrassLoader.cpp.

◆ setSwayDistribution()

void Forests::GrassLayer::setSwayDistribution ( Ogre::Real freq )

inline

Sets the smooth distribution (positional phase shift) of the grass swaying animation.

If you set this to 0, grass animation will look very unnatural, since all the grass sway motions will be in perfect synchronization (everything sways to the right, then everything sways to the left, etc.) This sets the "positional phase shift", which gives the grass a "wave" like phase distribution. The higher this value is, the more "chaotic" the wind will appear. Lower values give a smoother breeze appearance, but values too high can look unrealistic.

Definition at line 480 of file GrassLoader.h.

◆ setSwayLength()

void Forests::GrassLayer::setSwayLength ( Ogre::Real mag )

inline

Sets how far grass should sway back and forth.

Note: Since this is measured in world units, you may have to adjust this depending on the size of your grass as set by setMinimumSize() and setMaximumSize().

Definition at line 467 of file GrassLoader.h.

◆ setSwaySpeed()

void Forests::GrassLayer::setSwaySpeed ( Ogre::Real speed )

inline

Sets the sway speed of the grass (measured in "sways-per-second")

Definition at line 470 of file GrassLoader.h.

Friends And Related Symbol Documentation

◆ GrassLoader

friend class GrassLoader

friend

Definition at line 483 of file GrassLoader.h.

Field Documentation

◆ animate

bool Forests::GrassLayer::animate

private

Definition at line 531 of file GrassLoader.h.

◆ animFreq

Ogre::Real Forests::GrassLayer::animFreq

private

Definition at line 532 of file GrassLoader.h.

◆ animMag

Ogre::Real Forests::GrassLayer::animMag

private

Definition at line 532 of file GrassLoader.h.

◆ animSpeed

Ogre::Real Forests::GrassLayer::animSpeed

private

Definition at line 532 of file GrassLoader.h.

◆ blend

bool Forests::GrassLayer::blend

private

Definition at line 531 of file GrassLoader.h.

◆ colorMap

ColorMap* Forests::GrassLayer::colorMap

private

Definition at line 527 of file GrassLoader.h.

◆ colorMapFilter

MapFilter Forests::GrassLayer::colorMapFilter

private

Definition at line 528 of file GrassLoader.h.

◆ density

Ogre::Real Forests::GrassLayer::density

private

Definition at line 511 of file GrassLoader.h.

◆ densityMap

DensityMap* Forests::GrassLayer::densityMap

private

Definition at line 524 of file GrassLoader.h.

◆ densityMapFilter

MapFilter Forests::GrassLayer::densityMapFilter

private

Definition at line 525 of file GrassLoader.h.

◆ fadeTechnique

FadeTechnique Forests::GrassLayer::fadeTechnique

private

Definition at line 518 of file GrassLoader.h.

◆ geom

PagedGeometry* Forests::GrassLayer::geom

private

Definition at line 537 of file GrassLoader.h.

◆ lighting

bool Forests::GrassLayer::lighting

private

Definition at line 531 of file GrassLoader.h.

◆ mapBounds

TBounds Forests::GrassLayer::mapBounds

private

Definition at line 522 of file GrassLoader.h.

◆ material

Ogre::MaterialPtr Forests::GrassLayer::material

private

Definition at line 510 of file GrassLoader.h.

◆ maxHeight

Ogre::Real Forests::GrassLayer::maxHeight

private

Definition at line 513 of file GrassLoader.h.

◆ maxSlope

Ogre::Real Forests::GrassLayer::maxSlope

private

Definition at line 516 of file GrassLoader.h.

◆ maxWidth

Ogre::Real Forests::GrassLayer::maxWidth

private

Definition at line 512 of file GrassLoader.h.

◆ maxY

Ogre::Real Forests::GrassLayer::maxY

private

Definition at line 515 of file GrassLoader.h.

◆ minHeight

Ogre::Real Forests::GrassLayer::minHeight

private

Definition at line 513 of file GrassLoader.h.

◆ minWidth

Ogre::Real Forests::GrassLayer::minWidth

private

Definition at line 512 of file GrassLoader.h.

◆ minY

Ogre::Real Forests::GrassLayer::minY

private

Definition at line 515 of file GrassLoader.h.

◆ parent

GrassLoader* Forests::GrassLayer::parent

private

Definition at line 507 of file GrassLoader.h.

◆ renderTechnique

GrassTechnique Forests::GrassLayer::renderTechnique

private

Definition at line 519 of file GrassLoader.h.

◆ shaderNeedsUpdate

bool Forests::GrassLayer::shaderNeedsUpdate

private

Definition at line 531 of file GrassLoader.h.

◆ waveCount

Ogre::Real Forests::GrassLayer::waveCount

private

Definition at line 535 of file GrassLoader.h.

The documentation for this class was generated from the following files:

source/main/terrain/paged/GrassLoader.h
source/main/terrain/paged/GrassLoader.cpp

Description

Public Member Functions

Private Member Functions

Private Attributes

Friends

Constructor & Destructor Documentation

◆ GrassLayer()

◆ ~GrassLayer()

Member Function Documentation

◆ _populateGrassList_BilinearDM()

◆ _populateGrassList_UnfilteredDM()

◆ _populateGrassList_Uniform()

◆ _updateShaders()

◆ getBlendValue()

◆ getColorMap()

◆ getDensityMap()

◆ getLightingEnabled()

◆ getMapBounds()

◆ getMaxSlope()

◆ getParentGrassLoader()

◆ setAnimationEnabled()

◆ setColorMap() [1/2]

◆ setColorMap() [2/2]

◆ setColorMapFilter()

◆ setDensity()

◆ setDensityMap() [1/2]

◆ setDensityMap() [2/2]

◆ setDensityMapFilter()

◆ setFadeTechnique()

◆ setHeightRange()

◆ setLightingEnabled()

◆ setMapBounds()

◆ setMaterialName()

◆ setMaximumSize()

◆ setMaxSlope() [1/2]

◆ setMaxSlope() [2/2]

◆ setMinimumSize()

◆ setRenderTechnique()

◆ setSwayDistribution()

◆ setSwayLength()

◆ setSwaySpeed()

Friends And Related Symbol Documentation

◆ GrassLoader

Field Documentation

◆ animate

◆ animFreq

◆ animMag

◆ animSpeed

◆ blend

◆ colorMap

◆ colorMapFilter

◆ density

◆ densityMap

◆ densityMapFilter

◆ fadeTechnique

◆ geom

◆ lighting

◆ mapBounds

◆ material

◆ maxHeight

◆ maxSlope

◆ maxWidth

◆ maxY

◆ minHeight

◆ minWidth

◆ minY

◆ parent

◆ renderTechnique

◆ shaderNeedsUpdate

◆ waveCount