path: root/doc/python_api/rst/bge.texture.rst

Game Engine bge.texture Module
==============================

.. note::
	This documentation is still very weak, and needs some help! Right now they are mostly a collection
	of the docstrings found in the bge.texture source code + some random places filled with text.

*****
Intro
*****

The bge.texture module allows you to manipulate textures during the game.

Several sources for texture are possible: video files, image files, video capture, memory buffer, camera render or a mix of that.

The video and image files can be loaded from the internet using an URL instead of a file name.

In addition, you can apply filters on the images before sending them to the GPU, allowing video effect: blue screen, color band, gray, normal map.

bge.texture uses FFmpeg to load images and videos. All the formats and codecs that FFmpeg supports are supported by this module, including but not limited to::

	* AVI
	* Ogg
	* Xvid
	* Theora
	* dv1394 camera
	* video4linux capture card (this includes many webcams)
	* videoForWindows capture card (this includes many webcams)
	* JPG 

The principle is simple: first you identify a texture on an existing object using 
the :materialID: function, then you create a new texture with dynamic content
and swap the two textures in the GPU.

The GE is not aware of the substitution and continues to display the object as always, 
except that you are now in control of the texture.

When the texture object is deleted, the new texture is deleted and the old texture restored.

.. module:: bge.texture

.. class:: VideoFFmpeg(file [, capture=-1, rate=25.0, width=0, height=0])

	FFmpeg video source
   
	.. attribute:: status
		video status
		
	.. attribute::  range
		replay range
		
	.. attribute:: repeat
		repeat count, -1 for infinite repeat
		
		:type: int
	
	.. attribute:: framerate
		frame rate
		
		:type: float
		
	.. attribute:: valid
		Tells if an image is available
		
		:type: bool
		
	.. attribute:: image
		image data
		
	.. attribute:: size
		image size
		
	.. attribute:: scale
		fast scale of image (near neighbour)
		
	.. attribute:: flip
		flip image vertically
		
	.. attribute:: filter
		pixel filter
		
	.. attribute:: preseek
		number of frames of preseek
		
		:type: int
		
	.. attribute:: deinterlace
		deinterlace image
		
		:type: bool
   
	.. method:: play()
		Play (restart) video
		
	.. method:: pause()
		pause video
		
	.. method:: stop()
		stop video (play will replay it from start)
		
	.. method:: refresh()
		Refresh video - get its status

.. class:: ImageFFmpeg(file)

	FFmpeg image source
	
	.. attribute:: status
		video status
	
	.. attribute:: valid
		Tells if an image is available
		
		:type: bool
		
	.. attribute:: image
		image data
		
	.. attribute:: size
		image size
		
	.. attribute:: scale
		fast scale of image (near neighbour)
		
	.. attribute:: flip
		flip image vertically
		
	.. attribute:: filter
		pixel filter
		
	.. method:: refresh()
		Refresh image, i.e. load it
		
	.. method:: reload([newname])
		Reload image, i.e. reopen it
		
.. class:: ImageBuff()
	
	Image source from image buffer
	
	.. attribute:: filter
		pixel filter
	
	.. attribute:: flip
		flip image vertically
	
	.. attribute:: image
		image data
	
	.. method:: load(imageBuffer, width, height)
		Load image from buffer
	
	.. method:: plot(imageBuffer, width, height, positionX, positionY)
		update image buffer
	
	.. attribute:: scale
		fast scale of image (near neighbour)
	
	.. attribute:: size
		image size
	
	.. attribute:: valid
		bool to tell if an image is available

.. class:: ImageMirror(scene)
	
	Image source from mirror
	
	.. attribute:: alpha
		use alpha in texture
	
	.. attribute:: background
		background color
	
	.. attribute:: capsize
		size of render area
	
	.. attribute:: clip
		clipping distance
	
	.. attribute:: filter
		pixel filter
	
	.. attribute:: flip
		flip image vertically
	
	.. attribute:: image
		image data
	
	.. method:: refresh(imageMirror)
		Refresh image - invalidate its current content
	
	.. attribute:: scale
		fast scale of image (near neighbour)
	
	.. attribute:: size
		image size
	
	.. attribute:: valid
		bool to tell if an image is available
	
	.. attribute:: whole
		use whole viewport to render

.. class:: ImageMix()
	
	Image mixer
	
	.. attribute:: filter
		pixel filter
	
	.. attribute:: flip
		flip image vertically
	
	.. method:: getSource(imageMix)
		get image source
	
	.. method:: getWeight(imageMix)
		get image source weight
	
	.. attribute:: image
		image data
	
	.. method:: refresh(imageMix)
		Refresh image - invalidate its current content
	
	.. attribute:: scale
		fast scale of image (near neighbour)
	
	.. method:: setSource(imageMix)
		set image source
	
	.. method:: setWeight(imageMix)
		set image source weight
	
	.. attribute:: valid
		bool to tell if an image is available

.. class:: ImageRender(scene, camera)
	
	Image source from render
	
	.. attribute:: alpha
		use alpha in texture
	
	.. attribute:: background
		background color
	
	.. attribute:: capsize
		size of render area
	
	.. attribute:: filter
		pixel filter
	
	.. attribute:: flip
		flip image vertically
	
	.. attribute:: image
		image data
	
	.. method:: refresh(imageRender)
		Refresh image - invalidate its current content
	
	.. attribute:: scale
		fast scale of image (near neighbour)
	
	.. attribute:: size
		image size
	
	.. attribute:: valid
		bool to tell if an image is available
	
	.. attribute:: whole
		use whole viewport to render

.. class:: ImageViewport()
	
	Image source from viewport
	
	.. attribute:: alpha
		use alpha in texture
	
	.. attribute:: capsize
		size of viewport area being captured
	
	.. attribute:: filter
		pixel filter
	
	.. attribute:: flip
		flip image vertically
	
	.. attribute:: image
		image data
	
	.. attribute:: position
		upper left corner of captured area
	
	.. method:: refresh(imageViewport)
		Refresh image - invalidate its current content
	
	.. attribute:: scale
		fast scale of image (near neighbour)
	
	.. attribute:: size
		image size
	
	.. attribute:: valid
		bool to tell if an image is available
	
	.. attribute:: whole
		use whole viewport to capture

.. class:: Texture(gameObj)
	
	Texture objects
	
	.. attribute:: bindId
		OpenGL Bind Name
	
	.. method:: close(texture)
		Close dynamic texture and restore original
	
	.. attribute:: mipmap
		mipmap texture
	
	.. method:: refresh(texture)
		Refresh texture from source
	
	.. attribute:: source
		source of texture

.. class:: FilterBGR24()
	
	Source filter BGR24 objects

.. class:: FilterBlueScreen()
	
	Filter for Blue Screen objects
	
	.. attribute:: color
		blue screen color
	
	.. attribute:: limits
		blue screen color limits
	
	.. attribute:: previous
		previous pixel filter

.. class:: FilterColor()
	
	Filter for color calculations
	
	.. attribute:: matrix
		matrix [4][5] for color calculation
	
	.. attribute:: previous
		previous pixel filter

.. class:: FilterGray()
	
	Filter for gray scale effect
	
	.. attribute:: previous
		previous pixel filter

.. class:: FilterLevel()
	
	Filter for levels calculations
	
	.. attribute:: levels
		levels matrix [4] (min, max)
	
	.. attribute:: previous
		previous pixel filter

.. class:: FilterNormal()
	
	Filter for Blue Screen objects
	
	.. attribute:: colorIdx
		index of color used to calculate normal (0 - red, 1 - green, 2 - blue)
	
	.. attribute:: depth
		depth of relief
	
	.. attribute:: previous
		previous pixel filter

.. class:: FilterRGB24()
	
	Returns a new input filter object to be used with :class:'ImageBuff' object when the image passed
	to the ImageBuff.load() function has the 3-bytes pixel format BGR.

.. class:: FilterRGBA32()
	
	Source filter RGBA32 objects

.. function:: getLastError()
	Last error that occurred in a bge.texture function.
	
	:return: the description of the last error occurred in a bge.texture function.
	:rtype: string
	
.. function:: imageToArray(image,mode)
	Returns a :class:`~bgl.buffer` corresponding to the current image stored in a texture source object.

	:arg image: Image source object.
	:type image: object of type :class:'VideoFFmpeg', :class:'ImageFFmpeg', :class:'ImageBuff', :class:'ImageMix', :class:'ImageRender', :class:'ImageMirror' or :class:'ImageViewport'
	:arg mode: optional argument representing the pixel format. 
|	             You can use the characters R, G, B for the 3 color channels, A for the alpha channel, 
|	             0 to force a fixed 0 color channel and 1 to force a fixed 255 color channel.
|	             Example: "BGR" will return 3 bytes per pixel with the Blue, Green and Red channels in that order. 
|	                      "RGB1" will return 4 bytes per pixel with the Red, Green, Blue channels in that order and the alpha channel forced to 255.
|	             The default mode is "RGBA".

	:type mode: string
	:rtype: :class:`~bgl.buffer`
	:return: A object representing the image as one dimensional array of bytes of size (pixel_size*width*height),
	line by line starting from the bottom of the image. The pixel size and format is determined by the mode 
	parameter.
	
.. function materialID(object,name)
	Returns a numeric value that can be used in :class:'Texture' to create a dynamic texture.

	The value corresponds to an internal material number that uses the texture identified
	by name. name is a string representing a texture name with IM prefix if you want to
	identify the texture directly. 	This method works for basic tex face and for material,
	provided the material has a texture channel using that particular texture in first
	position of the texture stack. 	name can also have MA prefix if you want to identify
	the texture by material. In that case the material must have a texture channel in first
	position.
	
	If the object has no material that matches name, it generates a runtime error. Use try/except to catch the exception.
	
	Ex: bge.texture.materialID(obj, 'IMvideo.png')
	
	:arg object: the game object that uses the texture you want to make dynamic
	:type object: game object
	:arg name: name of the texture/material you want to make dynamic. 
	:type name: string
	:rtype: integer

.. function setLogFile(filename)
	Sets the name of a text file in which runtime error messages will be written, in addition to the printing
	of the messages on the Python console. Only the runtime errors specific to the VideoTexture module
	are written in that file, ordinary runtime time errors are not written. 

	:arg filename: name of error log file
	:type filename: string
	:rtype: integer