PictureEffects Xojo Plugin |

# MapEffect Class

The map effect is a low level effect for developers to make simple pixel mapping. This effect does the same as the REALbasic's built in RGBSurface.Transform function, except this class makes use of the PictureEffects multi-core processing.
Applies a one-to-one pixel transformation to all pixels of an RGBSurface.
Specify the transformation via either of three lookup tables, red, green, and blue, or one lookup table to apply to all three channels.
Each map parameter is an 256 element array of UInt8. The transformation works as follows: For each pixel, the pixel’s RGB value is used as an index into the map arrays and the value found becomes the new R, G, or B value for the pixel.
For example, if you set up a map such that red(i)=255-i, then using this function will invert the image.

MPImageFilter
MapEffect

class MapEffect

#### Properties

IgnoreAlpha | If set to true then the alpha channel of the source image will not be included in the destination image.
CPUCoreCount (Inherited) (console safe) | Returns number of detected CPU cores on the running machine.
ErrorCode (Inherited) (console safe) | Returns error code after applying the effect. This value is a Constant defined in the PictureEffectsError module.
MultiprocessingHint (Inherited) (console safe) | Use this property to fine tune CPU usage for this algorithm. By default this property is set to zero (Automatic). This property accepts all constants that are defined in this class.
ProgressHandler (Inherited) (console safe) | Use this property to use a progress class to get progress feedback from this function. This class must be a class that Implements the IProgressHandler Interface which is defined in this plugin.

#### Methods

Apply | Applies the effect on a given source image with a given mask.
ApplyInPlace | Applies the effect on a given source image with a given mask without creating a new image, the result is written into the source image. Very Important read the remarks.

#### Constants

CPU_USE_MACHINE_CORE_COUNT = -1 (Inherited) | Uses exactly the number of available CPU cores in the machine. (Available here means on-line CPU cores, some laptops can put CPU cores off line in low battery situations)
CPU_USE_AUTOMATIC = 0 (Inherited) | Takes into account number of available CPU cores on the Machine and also tries to select the fastest way based on developer rating for each algorithm and picture size. (In simple algorithms then the fastest path is sometimes 2 or 3 CPU cores and not 4 CPU cores because of the overhead of managing multiple cores). In more complex algorithms then 3 or 4 cores are almost always faster than 2 cores.
CPU_USE_1_CORE = 1 (Inherited) | Uses one CPU core.
CPU_USE_2_CORES = 2 (Inherited) | Uses two CPU cores. This setting will also work on machines with less than two CPU cores, but it will be slower or best case same speed as using the correct setting for such machine.
CPU_USE_3_CORES = 3 (Inherited) | Uses three CPU cores. This setting will also work on machines with less than three CPU cores, but it will be slower or best case same speed as using the correct setting for such machine.
CPU_USE_4_CORES = 4 (Inherited) | Uses four CPU cores. This setting will also work on machines with less than four CPU cores, but it will be slower or best case same speed as using the correct setting for such machine.
CPU_USE_5_CORES = 5 (Inherited) | Uses five CPU cores. This setting will also work on machines with less than four CPU cores, but it will be slower or best case same speed as using the correct setting for such machine.
CPU_USE_6_CORES = 6 (Inherited) | Uses six CPU cores. This setting will also work on machines with less than four CPU cores, but it will be slower or best case same speed as using the correct setting for such machine.
CPU_USE_7_CORES = 7 (Inherited) | Uses seven CPU cores. This setting will also work on machines with less than four CPU cores, but it will be slower or best case same speed as using the correct setting for such machine.
CPU_USE_8_CORES = 8 (Inherited) | Uses eight CPU cores. This setting will also work on machines with less than four CPU cores, but it will be slower or best case same speed as using the correct setting for such machine.

#### Example

Dim pic as Picture
Dim effect as MapEffect
Dim i as Integer
Dim mapping(255) as UInt8
if m_Picture = nil then
return
end if
effect = new MapEffect()
// Do a simple Invert mapping
for i = 0 to 255
mapping(i) = 255-i
next
m_DistortedImage = effect.Apply(m_Picture,mapping,mapping,mapping,nil)

#### Supported Platforms:

- MacOS X Carbon
- MacOS X Cocoa 32 bit
- MacOS X Cocoa 64 bit
- Windows 32 bit
- Windows 64 bit
- Linux 32 bit
- Linux 64 bit
- Linux ARM