Add support for sRGB attribute and fix creation on windows

src/lib.rs

@@ -253,6 +253,7 @@ pub struct BuilderAttribs<'a> {
     color_bits: Option<u8>,
     alpha_bits: Option<u8>,
     stereoscopy: bool,
+    srgb: Option<bool>,
 }
 
 impl BuilderAttribs<'static> {
@@ -274,6 +275,7 @@ impl BuilderAttribs<'static> {
             color_bits: None,
             alpha_bits: None,
             stereoscopy: false,
+            srgb: None,
         }
     }
 }
@@ -299,6 +301,7 @@ impl<'a> BuilderAttribs<'a> {
             color_bits: self.color_bits,
             alpha_bits: self.alpha_bits,
             stereoscopy: self.stereoscopy,
+            srgb: self.srgb,
         };
 
         (new_attribs, sharing)
@@ -332,6 +335,16 @@ impl<'a> BuilderAttribs<'a> {
                 continue;
             }
 
+            if self.multisampling.is_some() && format.multisampling.is_none() {
+                continue;
+            }
+
+            if let Some(srgb) = self.srgb {
+                if srgb != format.srgb {
+                    continue;
+                }
+            }
+
             current_software_result = Some((id.clone(), format.clone()));
             if format.hardware_accelerated {
                 current_result = Some((id, format));