Image dimming and gradient drawing added

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/gui/trunk@19721 72102866-910b-0410-8b05-ffd578937521

Source/NSButtonCell.m

@@ -41,6 +41,7 @@
 
 #include "AppKit/AppKitExceptions.h"
 #include "AppKit/NSApplication.h"
+#include "AppKit/NSBezierPath.h"
 #include "AppKit/NSButtonCell.h"
 #include "AppKit/NSButton.h"
 #include "AppKit/NSColor.h"
@@ -52,6 +53,8 @@
 #include "AppKit/NSWindow.h"
 #include "GNUstepGUI/GSDrawFunctions.h"
 
+#include <math.h>
+
 @implementation NSButtonCell
 
 /*
@@ -82,6 +85,8 @@
   _keyEquivalentModifierMask = NSCommandKeyMask;
   _keyEquivalent = @"";
   _altContents = @"";
+  _gradient_type = NSGradientNone;
+  _image_dims_when_disabled = NO;
 
   return self;
 }
@@ -653,6 +658,105 @@
   [self drawInteriorWithFrame: cellFrame inView: controlView];
 }
 
+- (void) drawGradientWithFrame: (NSRect)cellFrame inView: (NSView *)controlView
+{
+  float   start_white = 0.0;
+  float   end_white = 0.0;
+  float   white = 0.0;
+  float   white_step = 0.0;
+  float   h, s, v, a;
+  NSColor *lightGray = nil;
+  NSColor *gray = nil;
+  NSColor *darkGray = nil;
+  NSPoint p1, p2;
+
+  lightGray = [NSColor colorWithDeviceRed:0.83 green:0.83 blue:0.83 alpha:1.0];
+  gray = [NSColor colorWithDeviceRed:0.50 green:0.50 blue:0.50 alpha:1.0];
+  darkGray = [NSColor colorWithDeviceRed:0.32 green:0.32 blue:0.32 alpha:1.0];
+
+  switch (_gradient_type)
+    {
+    case NSGradientNone:
+      return;
+      break;
+
+    case NSGradientConcaveWeak:
+      [gray getHue: &h saturation: &s brightness: &v alpha: &a];
+      start_white = [lightGray brightnessComponent];
+      end_white = [gray brightnessComponent];
+      break;
+      
+    case NSGradientConvexWeak:
+      [darkGray getHue: &h saturation: &s brightness: &v alpha: &a];
+      start_white = [gray brightnessComponent];
+      end_white = [lightGray brightnessComponent];
+      break;
+      
+    case NSGradientConcaveStrong:
+      [lightGray getHue: &h saturation: &s brightness: &v alpha: &a];
+      start_white = [lightGray brightnessComponent];
+      end_white = [darkGray brightnessComponent];
+      break;
+      
+    case NSGradientConvexStrong:
+      [darkGray getHue: &h saturation: &s brightness: &v alpha: &a];
+      start_white = [darkGray brightnessComponent];
+      end_white = [lightGray brightnessComponent];
+      break;
+
+    default:
+      break;
+    }
+
+  white = start_white;
+  white_step = fabs(start_white - end_white)/
+               (cellFrame.size.width + cellFrame.size.height);
+
+  // Start from top left
+  p1 = NSMakePoint(cellFrame.origin.x, 
+		   cellFrame.size.height + cellFrame.origin.y);
+  p2 = NSMakePoint(cellFrame.origin.x, 
+		   cellFrame.size.height + cellFrame.origin.y);
+
+  // Move by Y
+  while (p1.y > cellFrame.origin.y)
+    {
+      [[NSColor 
+	colorWithDeviceHue: h saturation: s brightness: white alpha: 1.0] set];
+      [NSBezierPath strokeLineFromPoint: p1 toPoint: p2];
+      
+      if (start_white > end_white)
+	white -= white_step;
+      else
+	white += white_step;
+
+      p1.y -= 1.0;
+      if (p2.x < (cellFrame.size.width + cellFrame.origin.x))
+	p2.x += 1.0;
+      else
+	p2.y -= 1.0;
+    }
+      
+  // Move by X
+  while (p1.x < (cellFrame.size.width + cellFrame.origin.x))
+    {
+      [[NSColor 
+	colorWithDeviceHue: h saturation: s brightness: white alpha: 1.0] set];
+      [NSBezierPath strokeLineFromPoint: p1 toPoint: p2];
+      
+      if (start_white > end_white)
+	white -= white_step;
+      else
+	white += white_step;
+
+      p1.x += 1.0;
+      if (p2.x >= (cellFrame.size.width + cellFrame.origin.x))
+	p2.y -= 1.0;
+      else
+	p2.x += 1.0;
+    }
+}
+
 - (void) drawInteriorWithFrame: (NSRect)cellFrame inView: (NSView*)controlView
 {
   unsigned	mask;
@@ -877,6 +981,14 @@
 	// TODO: Add distance from border if needed
 	break;
     }
+
+  // Draw gradient
+  if (!_cell.is_highlighted && _gradient_type != NSGradientNone)
+    {
+      [self drawGradientWithFrame: cellFrame inView: controlView];
+    }
+    
+  // Draw image
   if (imageToDisplay != nil)
     {
       NSSize size;
@@ -893,13 +1005,25 @@
 	{
 	  position.y += size.height;
 	}
-      [imageToDisplay compositeToPoint: position operation: NSCompositeSourceOver];
+	
+      if (_cell.is_disabled && _image_dims_when_disabled)
+	{
+	  [imageToDisplay dissolveToPoint: position fraction: 0.5];
 	}
+      else
+	{
+	  [imageToDisplay compositeToPoint: position 
+	                         operation: NSCompositeSourceOver];
+	}
+    }
+
+  // Draw title
   if (titleToDisplay != nil)
     {
       [self _drawAttributedText: titleToDisplay inFrame: titleRect];
     }
 
+  // Draw first responder
   if (_cell.shows_first_responder
       && [[controlView window] firstResponder] == controlView)
     {