msdf.hlsl changes

Author: Erfan-Ahmadi

include/nbl/builtin/hlsl/text_rendering/msdf.hlsl

@@ -23,7 +23,7 @@ This can then be processed using smoothstep to provide anti-alising when renderi
 @params:
 - msdfSample: sampled SNORM value from the MSDF texture generated by msdfgen library.
 
-- pixelRange = msdfPixelRange * screenPxRangeValue, It is the value to convert snorm distance to screen space distance
+- pixelRange = screenPxRangeValue * msdfPixelRange * 0.5, It is the value to convert snorm distance to screen space distance
     - msdfPixelRange: specifies the width of the range around the shape between the minimum and maximum representable signed distance in shape units or distance field pixels, respectivelly.
         for example if msdfPixelRange is 4, then the range of distance values are [-2, +2], and it can be computed by snormValue * MSDFPixelRange/2.0
         so an snorm value of 1.0 means a distance of 2 pixels outside the shape (in msdf texture space)
@@ -34,7 +34,7 @@ This can then be processed using smoothstep to provide anti-alising when renderi
          where GlyphTextureSpaceSize is the size of the glyph inside the msdf texture/atlas
 */
 float msdfDistance(float3 msdfSample, float pixelRange) {
-    return median(msdfSample.r, msdfSample.g, msdfSample.b) * pixelRange / 2.0f;
+    return median(msdfSample.r, msdfSample.g, msdfSample.b) * pixelRange;
 }
 
 }