1 /*************************************************************************** 2 * Copyright (c) 2024 Microsoft Corporation 3 * 4 * This program and the accompanying materials are made available under the 5 * terms of the MIT License which is available at 6 * https://opensource.org/licenses/MIT. 7 * 8 * SPDX-License-Identifier: MIT 9 **************************************************************************/ 10 11 12 /**************************************************************************/ 13 /**************************************************************************/ 14 /** */ 15 /** GUIX Component */ 16 /** */ 17 /** Display Management (Display) */ 18 /** */ 19 /**************************************************************************/ 20 21 #define GX_SOURCE_CODE 22 23 24 /* Include necessary system files. */ 25 26 #include "gx_api.h" 27 #include "gx_system.h" 28 #include "gx_utility.h" 29 #include "gx_display.h" 30 31 32 /**************************************************************************/ 33 /* */ 34 /* FUNCTION RELEASE */ 35 /* */ 36 /* _gx_display_driver_4bpp_glyph_4bit_draw PORTABLE C */ 37 /* 6.1 */ 38 /* AUTHOR */ 39 /* */ 40 /* Kenneth Maxwell, Microsoft Corporation */ 41 /* */ 42 /* DESCRIPTION */ 43 /* */ 44 /* This draws the specified text using the current context, */ 45 /* clipped to one viewport */ 46 /* */ 47 /* INPUT */ 48 /* */ 49 /* context Draw context */ 50 /* draw_position The X and Y coordinate where */ 51 /* the glyph is drawn to */ 52 /* string String to draw */ 53 /* count Count of string characters */ 54 /* view view to clip drawing within */ 55 /* */ 56 /* OUTPUT */ 57 /* */ 58 /* None */ 59 /* */ 60 /* CALLS */ 61 /* */ 62 /* None */ 63 /* */ 64 /* CALLED BY */ 65 /* */ 66 /* _gx_canvas_text_draw */ 67 /* */ 68 /* RELEASE HISTORY */ 69 /* */ 70 /* DATE NAME DESCRIPTION */ 71 /* */ 72 /* 05-19-2020 Kenneth Maxwell Initial Version 6.0 */ 73 /* 09-30-2020 Kenneth Maxwell Modified comment(s), */ 74 /* resulting in version 6.1 */ 75 /* */ 76 /**************************************************************************/ _gx_display_driver_4bpp_glyph_4bit_draw(GX_DRAW_CONTEXT * context,GX_RECTANGLE * draw_area,GX_POINT * map_offset,const GX_GLYPH * glyph)77VOID _gx_display_driver_4bpp_glyph_4bit_draw(GX_DRAW_CONTEXT *context, GX_RECTANGLE *draw_area, GX_POINT *map_offset, const GX_GLYPH *glyph) 78 { 79 UINT row; 80 UINT height; 81 GX_VALUE index; 82 GX_UBYTE *glyph_getrow; 83 GX_UBYTE *glyphdata_get; 84 GX_UBYTE getmask; 85 GX_UBYTE text_color; 86 GX_UBYTE alpha; 87 GX_UBYTE *put; 88 GX_UBYTE putmask; 89 GX_UBYTE *draw_start; 90 INT putstride; 91 INT getstride; 92 93 putstride = (INT)(context -> gx_draw_context_pitch + 1) >> 1; 94 draw_start = (GX_UBYTE *)context -> gx_draw_context_memory; 95 draw_start += putstride * draw_area -> gx_rectangle_top; 96 draw_start += draw_area -> gx_rectangle_left >> 1; 97 98 text_color = (GX_UBYTE)(context -> gx_draw_context_brush.gx_brush_line_color + 15); 99 100 /* Find the width of the glyph */ 101 getstride = glyph -> gx_glyph_width; 102 /* Make it byte-aligned. */ 103 getstride = (getstride + 1) >> 1; 104 105 glyph_getrow = (GX_UBYTE *)glyph -> gx_glyph_map; 106 107 if (map_offset -> gx_point_y) 108 { 109 glyph_getrow = glyph_getrow + ((INT)getstride * map_offset -> gx_point_y); 110 } 111 112 glyph_getrow += (map_offset -> gx_point_x >> 1); 113 114 height = (UINT)(draw_area -> gx_rectangle_bottom - draw_area -> gx_rectangle_top + 1); 115 116 for (row = 0; row < height; row++) 117 { 118 glyphdata_get = glyph_getrow; 119 if (map_offset -> gx_point_x & 1) 120 { 121 getmask = 0x0f; 122 } 123 else 124 { 125 getmask = 0xf0; 126 } 127 128 put = draw_start; 129 if (draw_area -> gx_rectangle_left & 1) 130 { 131 putmask = 0x0f; 132 } 133 else 134 { 135 putmask = 0xf0; 136 } 137 138 for (index = draw_area -> gx_rectangle_left; index <= draw_area -> gx_rectangle_right; index++) 139 { 140 alpha = *glyphdata_get & getmask; 141 142 if (getmask == 0xf0) 143 { 144 alpha >>= 4; 145 getmask >>= 4; 146 } 147 else 148 { 149 glyphdata_get++; 150 getmask = 0xf0; 151 } 152 153 alpha = (GX_UBYTE)(text_color - alpha); 154 alpha |= (GX_UBYTE)(alpha << 4); 155 156 *put &= (GX_UBYTE)(~putmask); 157 *put |= (alpha & putmask); 158 159 putmask >>= 4; 160 if (putmask == 0) 161 { 162 putmask = 0xf0; 163 put++; 164 } 165 166 } 167 168 glyph_getrow += getstride; 169 draw_start += putstride; 170 } 171 } 172 173
