diff options
Diffstat (limited to 'olpcgames/_cairoimage.py')
| -rwxr-xr-x | olpcgames/_cairoimage.py | 135 |
1 files changed, 0 insertions, 135 deletions
diff --git a/olpcgames/_cairoimage.py b/olpcgames/_cairoimage.py deleted file mode 100755 index 3cfa22c..0000000 --- a/olpcgames/_cairoimage.py +++ /dev/null @@ -1,135 +0,0 @@ -"""Utility functions for cairo-specific operations - -USE_BASE_ARRAY -- if False (default), uses numpy arrays, - currently this is the only version that works on 32-bit - machines. -""" -import pygame, struct, logging -big_endian = struct.pack( '=i', 1 ) == struct.pack( '>i', 1 ) - -log = logging.getLogger( 'olpcgames._cairoimage' ) -##log.setLevel( logging.DEBUG ) - -USE_BASE_ARRAY = False - -def newContext( width, height ): - """Create a new render-to-image context - - width, height -- pixel dimensions to be rendered - - Produces an ARGB format Cairo ImageSurface for - rendering your data into using rsvg, Cairo or Pango. - - returns (ImageSurface, CairoContext) for rendering - """ - import cairo - csrf = cairo.ImageSurface(cairo.FORMAT_ARGB32, width, height) - context = cairo.Context (csrf) - #log.info( 'Format (expect: %s): %s', cairo.FORMAT_ARGB32, csrf.get_format()) - return csrf, context - -def mangle_color(color): - """Mange a colour depending on endian-ness, and swap-necessity - - Converts a 3 or 4 int (or float) value in the range 0-255 into a - 4-float value in the range 0.0-1.0 - """ - r,g,b = color[:3] - if len(color) > 3: - a = color[3] - else: - a = 255.0 - return map(_fixColorBase, (r,g,b,a) ) - -def _fixColorBase( v ): - """Return a properly clamped colour in floating-point space""" - return max((0,min((v,255.0))))/255.0 - -def asImage( csrf ): - """Get the pixels in csrf as a Pygame image - - Note that Pygame 1.7.1 on (Gentoo Linux) AMD64 is incorrectly - calculating the required size ARGB images, so this code will *not* work - on that platform with that version of the library. Pygame-ctypes - does work correctly there. - - Note also that Pygame 1.7.1 is showing a strange colour rotation - bug on 32-bit platforms, such that ARGB mode cannot be used for - images there. Instead we have to do an expensive bit-shift operation - to produce an RGBA image from the ARGB native Cairo format. - - Will raise a ValueError if passed a Null image (i.e. dimension of 0) - - returns Pygame.Surface (image) with convert_alpha() called for it. - """ - # Create and return a new Pygame Image derived from the Cairo Surface - format = 'ARGB' - if hasattr(csrf,'get_data'): - # more recent API, native-format, but have to (potentially) convert the format... - log.debug( 'Native-mode api (get_data)' ) - data = csrf.get_data() - if not big_endian: - # we use array here because it's considerably lighter-weight - # to import than the numpy module - log.debug( 'Not big-endian, byte-swapping array' ) - if USE_BASE_ARRAY: - import array - a = array.array( 'I' ) - a.fromstring( data ) - a.byteswap() - data = a.tostring() - else: - import numpy - n = numpy.fromstring( data, dtype='I' ) - n = ((n & 0xff000000) >> 24 ) | ((n & 0x00ffffff) << 8 ) - n = n.byteswap() - data = n.tostring() - format = 'RGBA' - else: - log.debug( 'Big-endian, array unchanged' ) - data = str(data) # there's one copy - else: - # older api, not native, but we know what it is... - log.debug( 'Non-native mode api, explicitly RGBA' ) - data = csrf.get_data_as_rgba() - data = str(data) # there's one copy - format = 'RGBA' - width, height = csrf.get_width(),csrf.get_height() - - try: - log.info( 'Format = %s', format ) - return pygame.image.fromstring( - data, - (width,height), - format - ) # there's the next - except ValueError, err: - err.args += (len(data), (width,height), width*height*4,format ) - raise - -if __name__ == "__main__": - import unittest - logging.basicConfig() - class Tests( unittest.TestCase ): - def test_colours( self ): - """Test that colours are correctly translated - - If we draw a given colour in cairo, we want the same - colour to show up in Pygame, let's test that... - """ - for sourceColour in [ - (255,0,0, 255), - (0,255,0, 255), - (0,0,255, 255), - (255,255,0, 255), - (0,255,255,255), - (255,0,255,255), - ]: - csrf,cctx = newContext( 1,1 ) - background = mangle_color( sourceColour ) - cctx.set_source_rgba(*background) - cctx.paint() - img = asImage( csrf ) - colour = img.get_at( (0,0)) - assert colour == sourceColour, (sourceColour,mangle_color(sourceColour),colour) - unittest.main() |