1 /* 2 * Copyright 2005, Stephan Aßmus <superstippi@gmx.de>. 3 * Copyright 2008, Andrej Spielmann <andrej.spielmann@seh.ox.ac.uk>. 4 * All rights reserved. Distributed under the terms of the MIT License. 5 * 6 * DrawingMode implementing B_OP_SUBTRACT on B_RGBA32. 7 * 8 */ 9 10 #ifndef DRAWING_MODE_SUBTRACT_SUBPIX_H 11 #define DRAWING_MODE_SUBTRACT_SUBPIX_H 12 13 #include "DrawingMode.h" 14 #include "GlobalSubpixelSettings.h" 15 16 // BLEND_SUBTRACT_SUBPIX 17 #define BLEND_SUBTRACT_SUBPIX(d, r, g, b, a1, a2, a3) \ 18 { \ 19 pixel32 _p; \ 20 _p.data32 = *(uint32*)d; \ 21 uint8 rt = max_c(0, _p.data8[2] - (r)); \ 22 uint8 gt = max_c(0, _p.data8[1] - (g)); \ 23 uint8 bt = max_c(0, _p.data8[0] - (b)); \ 24 BLEND_SUBPIX(d, rt, gt, bt, a1, a2, a3); \ 25 } 26 27 28 // blend_solid_hspan_subtract_subpix 29 void 30 blend_solid_hspan_subtract_subpix(int x, int y, unsigned len, 31 const color_type& c, const uint8* covers, agg_buffer* buffer, 32 const PatternHandler* pattern) 33 { 34 uint8* p = buffer->row_ptr(y) + (x << 2); 35 const int subpixelL = gSubpixelOrderingRGB ? 2 : 0; 36 const int subpixelM = 1; 37 const int subpixelR = gSubpixelOrderingRGB ? 0 : 2; 38 do { 39 rgb_color color = pattern->ColorAt(x, y); 40 BLEND_SUBTRACT_SUBPIX(p, color.red, color.green, color.blue, 41 covers[subpixelL], covers[subpixelM], covers[subpixelR]); 42 covers += 3; 43 p += 4; 44 x++; 45 len -= 3; 46 } while (len); 47 } 48 49 #endif // DRAWING_MODE_SUBTRACT_SUBPIX_H 50 51