Graphics rendering of rectangles to offscreen images slower than in 1.3

Name: pa48320 Date: 09/03/2002

bug 4527745 was marked closed/fixed in 1.4.1. However, with the latest build (19) we are seeing slow downs with drawing vertical lines, empty rectangles, and filled rectangles of about 3 times. The original bug mentioned clipping as an issue in the test. Our test should not have any clipping. Tests were made Onscreen vs Offscreen and the onscreen performance was way slower in 1.4.1. The following routines were used to test the problem:
public java.awt.Image image = null;
public boolean paintFlag = false;
public void paint(java.awt.Graphics g)
{


super.paint(g);
if (image == null)
image = createImage( 300, 250 );
if (!paintFlag)
return;
System.out.println("Graphics timing test on screen-"+System.getProperty("java.vm.version"));

drawImage(g);
System.out.println("Graphics timing test off screen-"+System.getProperty("java.vm.version"));
System.out.println(image.getClass().getName());
drawImage(image.getGraphics());

      // Blit the image.
      g.drawImage( image, 300, 0, this );
paintFlag = false;
}

public void drawImage(java.awt.Graphics ig)
{
      // Clear the image and draw the title.
      int maxShape = 3;
      int maxSize = 10;
      int maxIter = 200000;
      ig.clearRect( 0, 0, getWidth() / 2, getHeight());
int ymin = getInsets().top;
int xmin = getInsets().left;
      ig.drawString( "Time in milliseconds, " + maxIter + " markers:", xmin+2, ymin+12 );
      System.out.println( "Time in milliseconds, " + maxIter + " markers:" );
      int y0 = 0;
      // Draw all shapes.
      for( int shape = 0; ( shape < maxShape ); shape++ )
      {
if( shape == 0 )
         System.out.println("Vertical bars");
        else if( shape == 1 )
         System.out.println("Empty rectangles");
        else
         System.out.println("Filled rectangles");
         // Calculate the center.
         int x0 = 60 * ( shape % 10 ) + 10+xmin;
         y0 = ymin+25 + 250 * ( shape / 10 );
         
         // Draw all sizes.
         for( int size = 1; ( size <= maxSize ); size++ )
         {
            // Draw all iterations.
            int size2 = size / 2;
            long time0 = ( long )System.currentTimeMillis();
            for( int j = 0; ( j < maxIter ); j++ )
            { if( shape == 0 )
                  ig.drawLine( x0, y0 - size2, x0, y0 - size2 + size );
               else if( shape == 1 )
                  ig.drawRect( x0 - size2, y0 - size2, size, size );
               else
                  ig.fillRect( x0 - size2, y0 - size2, size, size );
            }
            
            // Draw the time.
            long time1 = ( long )System.currentTimeMillis();
            long time = ( time1 - time0 );
            String secs = "";
            for( int j = 10; ( j < 10000 ); j *= 10 )
            { if( time < j )
                  secs += " ";
            }
            secs += time;
            ig.drawString( secs, x0 + 7, y0 + 5 );
System.out.println(secs);
            y0 += 20;
         }
      }
}
This test produced the following timings:
Graphics timing test on screen-1.4.1-rc-b19
Time in milliseconds, 200000 markers:
Vertical bars
  750
  485
  500
  500
  485
  485
  500
  484
  500
  485
Empty rectangles
  515
1766
1703
1719
1750
1781
1734
1719
1703
1765
Filled rectangles
  500
  500
  485
  500
  484
  500
  485
  500
  484
  516
Graphics timing test off screen-1.4.1-rc-b19
Time in milliseconds, 200000 markers:
Vertical bars
  234
  234
  282
  250
  235
  250
  250
  281
  250
  250
Empty rectangles
  250
  250
  250
  250
  265
  282
  265
  266
  281
  281
Filled rectangles
  219
  219
  250
  234
  235
  234
  250
  266
  250
  250
Graphics timing test on screen-1.3.1_03-b03
Time in milliseconds, 200000 markers:
Vertical bars
2453
2313
2015
1938
1937
1985
1953
1984
1938
1938
Empty rectangles
3219
3203
3234
3219
3203
3187
3188
3219
3218
3204
Filled rectangles
1968
1969
1969
1969
1968
1969
1969
1953
1953
1953
Graphics timing test off screen-1.3.1_03-b03
Time in milliseconds, 200000 markers:
Vertical bars
  156
  188
  171
  172
  172
  188
  187
  203
  188
  203
Empty rectangles
  156
  156
  188
  172
  156
  188
  171
  188
  203
  188
Filled rectangles
  156
  156
  172
  187
  188
  187
  188
  203
  219
  250

======================================================================