[Pkg] The Trunk: Graphics-ul.133.mcz

[commits at source.squeak.org]

Levente Uzonyi uploaded a new version of Graphics to project The Trunk:
http://source.squeak.org/trunk/Graphics-ul.133.mcz

==================== Summary ====================

Name: Graphics-ul.133
Author: ul
Time: 28 April 2010, 11:26:50.367 am
UUID: d81b8f98-7b9a-c744-a652-229157d9445d
Ancestors: Graphics-laza.132

- integrated the png speedup changes and transparency fixes (by Juan)
- also kept Andreas' and Yoshiki's version in a comment at PNGReadWriter >> #copyPixelsGray:

=============== Diff against Graphics-laza.132 ===============

Item was changed:
  ----- Method: PNGReadWriter>>processTransparencyChunk (in category 'chunks') -----
  processTransparencyChunk
  
  	| red green blue |
  
  	"Transcript show: '  TRANSPARENCY ',chunk printString."
  	colorType = 0 ifTrue: [
  		transparentPixelValue := chunk unsignedShortAt: 1 bigEndian: true.
+ 		palette at: transparentPixelValue put: Color transparent.
  		^self
  	].
  	colorType = 2 ifTrue: [
  		red := chunk at: 2.
  		green := chunk at: 2.
  		blue := chunk at: 2.
  		transparentPixelValue := 16rFF00 + red << 8 + green << 8 + blue.
  		^self
  	].
  	colorType = 3 ifTrue: [
  		chunk withIndexDo: [ :alpha :index |
  			palette at: index put: ((palette at: index) alpha: alpha/255)
  		].
  		^self
  	].
  !

Item was changed:
  ----- Method: PNGReadWriter>>copyPixelsGray: (in category 'pixel copies') -----
  copyPixelsGray: y 
  	"Handle non-interlaced grayscale color mode (colorType = 0)"
+ 
+ 	| base bits |
+ 	bitsPerChannel = 16 ifTrue: [
+ 		"Warning: This is extremely slow. Besides we are downsampling to 8 bits!!"
+ 		| blitter |
+ 		blitter := BitBlt current bitPokerToForm: form.
+ 		0 to: width - 1 do: [ :x |
+ 			blitter pixelAt: x @ y put: 255 - (thisScanline at: x * 2 + 1) ].
+ 			^self ].
+ 
+ 	"Just copy the bits"
+ 
+ 	"This Smalltalk version might be easier to understand than the others below."
+ 	base := y * form width * bitsPerChannel // 32 + 1.
+ 	bits := form bits.
+ 	0 to: thisScanline size - 1 // 4 do: [ :i |
+ 		| ii word |
+ 		ii := i * 4.
+ 		"This somewhat weird mixture of (#* and #+) with (#bitShift: and #bitOr:) 
+ 		is to make use of faster arithmetic bytecodes, but not of slow largeintegers."
+ 		word :=
+ 			(((thisScanline at: ii + 1) * 256 + 
+ 			(thisScanline at: ii + 2) * 256 + 
+ 			(thisScanline at: ii + 3)) bitShift: 8) bitOr: 
+ 			(thisScanline at: ii + 4).
+ 		bits at: base + i put: word ].	
+ 	
+ 	"This interesting technique (By Andreas Raab) is faster for very large images, but might be slower for small ones"
+ 	"^self copyPixelsGrayWeirdBitBltHack: y ".
+ 	"It uses the following method:
+ 	PNGReadWriter >> copyPixelsGrayWeirdBitBltHack: y 
+ 	""Handle non-interlaced black and white color mode (colorType = 0)
+ 	By Andreas Raab""
+ 	
+ 	| source dest cmap |
+ 	source := Form extent: 1 @ (thisScanline size // 4) depth: 32 bits: thisScanline.
+ 	dest := Form extent: 1 @ (form bits size) depth: 32 bits: form bits.
+ 	cmap := Smalltalk isLittleEndian
+ 		ifTrue:[ColorMap 
+ 					shifts: #(-24 -8 8 24) 
+ 					masks: #(16rFF000000 16r00FF0000 16r0000FF00 16r000000FF)].
+ 	(BitBlt toForm: dest)
+ 		sourceForm: source;
+ 		destX: 0 destY: (y * form width*bitsPerChannel//32) width: 1 height: (form width+31*bitsPerChannel//32);
+ 		colorMap: cmap;
+ 		combinationRule: 3;
+ 		copyBits."
+ 		
+ 	"This interesting technique  (By Yoshiki Ohshima) is faster for very large images, but might be slower for small ones"
+ 	"form bits copyFromByteArray2: thisScanline to: y * (form width* bitsPerChannel // 32)".
+ 	"It uses the following method:
+ 	BitMap >> copyFromByteArray2: byteArray to: i
+ 	""This method should work with either byte orderings""
+ 
+ 	| myHack byteHack |
+ 	myHack := Form new hackBits: self.
+ 	byteHack := Form new hackBits: byteArray.
+ 	Smalltalk  isLittleEndian ifTrue: [byteHack swapEndianness].
+ 	byteHack displayOn: myHack at:  0 at i"!
- 	| blitter pixPerByte mask shifts pixelNumber rawByte pixel transparentIndex |
- 	blitter := BitBlt current bitPokerToForm: form.
- 	transparentIndex := form colors size.
- 	bitsPerChannel = 16
- 		ifTrue: [0
- 				to: width - 1
- 				do: [:x | blitter pixelAt: x @ y put: 255
- 							- (thisScanline at: x << 1 + 1)].
- 			^ self]
- 		ifFalse: [bitsPerChannel = 8
- 				ifTrue: [1
- 						to: width
- 						do: [:x | blitter
- 								pixelAt: x - 1 @ y
- 								put: (thisScanline at: x)].
- 					^ self].
- 			bitsPerChannel = 1
- 				ifTrue: [pixPerByte := 8.
- 					mask := 1.
- 					shifts := #(7 6 5 4 3 2 1 0 )].
- 			bitsPerChannel = 2
- 				ifTrue: [pixPerByte := 4.
- 					mask := 3.
- 					shifts := #(6 4 2 0 )].
- 			bitsPerChannel = 4
- 				ifTrue: [pixPerByte := 2.
- 					mask := 15.
- 					shifts := #(4 0 )].
- 			pixelNumber := 0.
- 			0 to: width - 1 do: [:x | 
- 				rawByte := thisScanline at: pixelNumber // pixPerByte + 1.
- 				pixel := rawByte
- 							>> (shifts at: pixelNumber \\ pixPerByte + 1) bitAnd: mask.
- 				pixel = transparentPixelValue ifTrue: [pixel := transparentIndex].
- 				blitter pixelAt: x @ y put: pixel.
- 				pixelNumber := pixelNumber + 1
- 			]
- 		]!

Item was changed:
  ----- Method: PNGReadWriter>>grayColorsFor: (in category 'miscellaneous') -----
  grayColorsFor: d
  	"return a color table for a gray image"
  
  	palette := Array new: 1<<d.
  	d = 1 ifTrue: [
  		palette at: 1 put: Color black.
  		palette at: 2 put: Color white.
+ 		^  palette
- 		^ palette,{Color transparent}
  		].
  	d = 2 ifTrue: [
  		palette at: 1 put: Color black.
  		palette at: 2 put: (Color gray: 85.0 / 255.0).
  		palette at: 3 put: (Color gray: 170.0 / 255.0).
  		palette at: 4 put: Color white.
+ 		^ palette
- 		^ palette,{Color transparent}.
  		].
  	d = 4 ifTrue: [
  		0 to: 15 do: [ :g |
  			palette at: g+1 put: (Color gray: (g/15) asFloat) ].
+ 		^ palette
- 		^ palette,{Color transparent}
  		].
  	d = 8 ifTrue: [
  		0 to: 255 do: [ :g |
  			palette at: g+1 put: (Color gray: (g/255) asFloat) ].
+ 		^ palette
- 		^ palette		"??transparent??"
  		].
  !