Adsk contrib - Convert to or from a known external color space (#1710)

* First iteration of isColorspaceLinear.

Signed-off-by: Cedrik Fuoco <[email protected]>

* - Comments.
- Added a private getProcessor method that ignore caching.
- Fix the algorithm for isColorspaceLinear. - Now testing R, G, B and neutral values.

Signed-off-by: Cedrik Fuoco <[email protected]>

* - Passing in the config reference instead of using this in the capture clause of the lambda function as this was causing issue on other platforms than Windows.
- Remove unused variable in unit test.
- other minors changes

Signed-off-by: Cedrik Fuoco <[email protected]>

* Removing a comment and removing the helper function as it is not needed.

Signed-off-by: Cedrik Fuoco <[email protected]>

* Get in sync with changes on the public repository for isColorspaceLinear.

Signed-off-by: Cedrik Fuoco <[email protected]>

* - C++ implemention for getProcessorToBuiltinColorSpace with a few utilitiy functions

Signed-off-by: Cedrik Fuoco <[email protected]>

* - Changed getProcessorToBuiltinColorSpace to getProcessorToOrFromBuiltinColorspace and it not accessible through the API anymore
- Added getProcessorFromBuiltInColorspace (API)
- Added getProcessorToBuiltinColorspace (API)
- rename "bi" variables to "builtin"
- Added the swaping of colorspace when TRANSFORM_DIR_INVERSE
- Added C++ unit test

std::cout debug print will be removed in the next commit.
Signed-off-by: Cedrik Fuoco <[email protected]>

* Adding ColorSpaceUtils

Signed-off-by: Cedrik Fuoco <[email protected]>

* - Comments and styling
- Refactor the code in order to use apply()
- Move everything to ColorSpaceUtils so that all the helper functions are private to ColorSpaceUtils
- Remove the std::cout

Signed-off-by: Cedrik Fuoco <[email protected]>

* Now using getProcessorWithoutCaching and moved logics into Config::Impl.

Signed-off-by: Cedrik Fuoco <[email protected]>

* Removing combineGroupTransform, small refactor of getRefToSRGBTransform and styling issues.

Signed-off-by: Cedrik Fuoco <[email protected]>

* Python Bindings

Signed-off-by: Cedrik Fuoco <[email protected]>

* Changing new helper methods to const and minor styling issues.

Signed-off-by: Cedrik Fuoco <[email protected]>

* Minor styling issues

Signed-off-by: Cedrik Fuoco <[email protected]>

* Changed a comment to fit on one line and styling issue.

Signed-off-by: Cedrik Fuoco <[email protected]>

* Removing extra qualifiers that returns an error on Linux and Mac and fixing warnings on Linux and Mac.

Signed-off-by: Cedrik Fuoco <[email protected]>

* Fixing issue with documentation

Signed-off-by: Cedrik Fuoco <[email protected]>

* - Rename checkForLinearColorSpace ---> getReferenceSpaceFromLinearSpace
- Fix an issue where the wrong config object was used for getProcessorWithoutCaching.
- Added a comment about about 0.0030399346397784323.
- Using std::pow instead of pow
- Small refactor of getReferenceSpaceFromLinearSpace to avoid duplicate code.

Signed-off-by: Cedrik Fuoco <[email protected]>

* Renaming checkForSRGBTextureColorSpace to getReferenceSpaceFromSRGBSpace and adding "Utility - Linear - Rec.2020" to the builtin linear spaces.

Signed-off-by: Cedrik Fuoco <[email protected]>

Signed-off-by: Cedrik Fuoco <[email protected]>
Signed-off-by: Cédrik Fuoco <[email protected]>

Author: cedrik-fuoco-adsk

include/OpenColorIO/OpenColorIO.h

@@ -1210,6 +1210,46 @@ class OCIOEXPORT Config
                                      const ConstTransformRcPtr & transform,
                                      TransformDirection direction) const;
 
+    /**
+     * \brief Get a Processor to or from a known external color space.
+     * 
+     * These methods provide a way to interface color spaces in a config with known standard 
+     * external color spaces. The set of external color space are those contained in the current 
+     * default Built-in config. This includes common spaces such as "Linear Rec.709 (sRGB)", 
+     * "sRGB - Texture", "ACEScg", and "ACES2065-1".
+     * 
+     * If the source config defines the necessary Interchange Role (typically "aces_interchange"), 
+     * then the conversion will be well-defined and equivalent to calling GetProcessorFromConfigs
+     * with the source config and the Built-in config
+     * 
+     * However, if the Interchange Roles are not present, heuristics will be used to try and 
+     * identify a common color space in the source config that may be used to allow the conversion 
+     * to proceed. If the heuristics fail to find a suitable space, an exception is thrown. 
+     * The heuristics may evolve, so the results returned by this function for a given source config 
+     * and color space may change in future releases of the library. However, the Interchange Roles 
+     * are required in config versions 2.2 and higher, so it is hoped that the need for the heuristics 
+     * will decrease over time.
+     * 
+     * \param srcConfig The user's source config.
+     * \param srcColorSpaceName The name of the color space in the source config.
+     * \param builtinColorSpaceName The name of the color space in the current default Built-in config.
+     */
+    static ConstProcessorRcPtr GetProcessorToBuiltinColorSpace(
+                                                                ConstConfigRcPtr srcConfig,
+                                                                const char * srcColorSpaceName, 
+                                                                const char * builtinColorSpaceName);
+    /**
+     * \brief See description of GetProcessorToBuiltinColorSpace.
+     * 
+     * \param builtinColorSpaceName The name of the color space in the current default Built-in config.
+     * \param srcConfig The user's source config.
+     * \param srcColorSpaceName The name of the color space in the source config. 
+     */
+    static ConstProcessorRcPtr GetProcessorFromBuiltinColorSpace(
+                                                                const char * builtinColorSpaceName,
+                                                                ConstConfigRcPtr srcConfig,
+                                                                const char * srcColorSpaceName);
+
     /**
      * \brief Get a processor to convert between color spaces in two separate
      *      configs.