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_ALPHA in "Pixel Overlay" mode on B_RGBA32.
7 *
8 */
9
10 #ifndef DRAWING_MODE_ALPHA_PO_SUBPIX_H
11 #define DRAWING_MODE_ALPHA_PO_SUBPIX_H
12
13 #include "DrawingMode.h"
14 #include "GlobalSubpixelSettings.h"
15
16 // BLEND_ALPHA_PO_SUBPIX
17 #define BLEND_ALPHA_PO_SUBPIX(d, r, g, b, a1, a2, a3) \
18 { \
19 BLEND16_SUBPIX(d, r, g, b, a1, a2, a3); \
20 }
21
22
23 // blend_solid_hspan_alpha_po_subpix
24 void
blend_solid_hspan_alpha_po_subpix(int x,int y,unsigned len,const color_type & c,const uint8 * covers,agg_buffer * buffer,const PatternHandler * pattern)25 blend_solid_hspan_alpha_po_subpix(int x, int y, unsigned len,
26 const color_type& c, const uint8* covers, agg_buffer* buffer,
27 const PatternHandler* pattern)
28 {
29 uint8* p = buffer->row_ptr(y) + (x << 2);
30 uint16 alphaRed;
31 uint16 alphaGreen;
32 uint16 alphaBlue;
33 const int subpixelL = gSubpixelOrderingRGB ? 2 : 0;
34 const int subpixelM = 1;
35 const int subpixelR = gSubpixelOrderingRGB ? 0 : 2;
36 do {
37 rgb_color color = pattern->ColorAt(x, y);
38 alphaRed = color.alpha * covers[subpixelL];
39 alphaGreen = color.alpha * covers[subpixelM];
40 alphaBlue = color.alpha * covers[subpixelR];
41 BLEND_ALPHA_PO_SUBPIX(p, color.red, color.green, color.blue,
42 alphaBlue, alphaGreen, alphaRed);
43 covers += 3;
44 p += 4;
45 x++;
46 len -= 3;
47 } while (len);
48 }
49
50 #endif // DRAWING_MODE_ALPHA_PO_SUBPIX_H
51
52