MCGR: Adapted GradientAxial to make use of MCGR

Added to make GradientAxial work using the MCGR
as 2nd of six types. This one was complicated
since it uses the gradient(s) 'reversed' when you
look at it, from outside to inside. Had to do
quite some tickeling to get it all work, but
looks good now.

For modifyBColor I Could re-use the started
tooling as planned.

To get the reverse usage working I ended up in
1st adapting the previous usage to make more use
of std::iterator and reverse_iterator to be able
to use the reversed state of the ColorSteps more
'controlled' as if trying to adapt the numerical
indices to the vector (that ended in chaos).

It is still 100% backward-compatible, so as long
as there is no source using this it will stay
invisible - by purpose.

Tests look good with this one, see the static
variable nUseGradientSteps.

Change-Id: I0117ec9a24b5e55869b3e2741c67fb87b549db97
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/147510
Tested-by: Jenkins
Reviewed-by: Armin Le Grand <Armin.Le.Grand@me.com>

1 files changed, 2 insertions, 16 deletions

diff --git a/basegfx/source/tools/gradienttools.cxx b/basegfx/source/tools/gradienttools.cxx
index 4aa909fcf58c..b27443898f4e 100644
--- a/basegfx/source/tools/gradienttools.cxx
+++ b/basegfx/source/tools/gradienttools.cxx
@@ -467,7 +467,7 @@ namespace basegfx
         {
             const B2DPoint aCoor(rGradInfo.getBackTextureTransform() * rUV);
 
-            // Ignore Y, this is not needed at all for Y-Oriented gradients
+            // Ignore X, this is not needed at all for Y-Oriented gradients
             // if(aCoor.getX() < 0.0 || aCoor.getX() > 1.0)
             // {
             //     return 0.0;
@@ -483,13 +483,6 @@ namespace basegfx
                 return 1.0; // end value for outside
             }
 
-            // const sal_uInt32 nSteps(rGradInfo.getRequestedSteps());
-
-            // if(nSteps)
-            // {
-            //     return floor(aCoor.getY() * nSteps) / double(nSteps - 1);
-            // }
-
             return aCoor.getY();
         }
 
@@ -497,7 +490,7 @@ namespace basegfx
         {
             const B2DPoint aCoor(rGradInfo.getBackTextureTransform() * rUV);
 
-            // Ignore Y, this is not needed at all for Y-Oriented gradients
+            // Ignore X, this is not needed at all for Y-Oriented gradients
             //if(aCoor.getX() < 0.0 || aCoor.getX() > 1.0)
             //{
             //    return 0.0;
@@ -510,13 +503,6 @@ namespace basegfx
                 return 1.0; // use end value when outside in Y
             }
 
-            const sal_uInt32 nSteps(rGradInfo.getRequestedSteps());
-
-            if(nSteps)
-            {
-                return floor(fAbsY * nSteps) / double(nSteps - 1);
-            }
-
             return fAbsY;
         }