| paul@78 | 1 | /* |
| paul@78 | 2 | * Common font-related functions. |
| paul@78 | 3 | * |
| paul@78 | 4 | * Copyright (C) 2018 Paul Boddie <paul@boddie.org.uk> |
| paul@78 | 5 | * |
| paul@78 | 6 | * This program is free software: you can redistribute it and/or modify |
| paul@78 | 7 | * it under the terms of the GNU General Public License as published by |
| paul@78 | 8 | * the Free Software Foundation, either version 3 of the License, or |
| paul@78 | 9 | * (at your option) any later version. |
| paul@78 | 10 | * |
| paul@78 | 11 | * This program is distributed in the hope that it will be useful, |
| paul@78 | 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| paul@78 | 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| paul@78 | 14 | * GNU General Public License for more details. |
| paul@78 | 15 | * |
| paul@78 | 16 | * You should have received a copy of the GNU General Public License |
| paul@78 | 17 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| paul@78 | 18 | */ |
| paul@78 | 19 | |
| paul@78 | 20 | #include <stdlib.h> |
| paul@78 | 21 | |
| paul@78 | 22 | #include "display.h" |
| paul@78 | 23 | #include "font.h" |
| paul@78 | 24 | |
| paul@78 | 25 | |
| paul@78 | 26 | |
| paul@132 | 27 | /* Space is a special case. */ |
| paul@132 | 28 | |
| paul@132 | 29 | static char_definition_t space = { |
| paul@132 | 30 | .width = 3, .height = 9, .data = {0, 0, 0, 0, 0, 0, 0, 0, 0} |
| paul@132 | 31 | }; |
| paul@132 | 32 | |
| paul@132 | 33 | |
| paul@132 | 34 | |
| paul@78 | 35 | /* Return the character definition for the given character. */ |
| paul@78 | 36 | |
| paul@78 | 37 | char_definition_t *get_char_definition(font_config_t *fcfg, char c) |
| paul@78 | 38 | { |
| paul@78 | 39 | /* Obtain the offset from the table and combine it with the character |
| paul@78 | 40 | definitions base address. */ |
| paul@78 | 41 | |
| paul@135 | 42 | if ((c >= fcfg->range->base) && (c < fcfg->range->limit)) |
| paul@135 | 43 | return (char_definition_t *) ((uint8_t *) fcfg->chars + fcfg->range->table[c - fcfg->range->base]); |
| paul@78 | 44 | else |
| paul@132 | 45 | return &space; |
| paul@78 | 46 | } |
| paul@78 | 47 | |
| paul@78 | 48 | /* Write a character to the screen, returning the next character position. */ |
| paul@78 | 49 | |
| paul@78 | 50 | int write_char(display_config_t *cfg, font_config_t *fcfg, char c, |
| paul@78 | 51 | int x, int y, uint8_t colour) |
| paul@78 | 52 | { |
| paul@78 | 53 | int sy, dx, dy; |
| paul@78 | 54 | char_definition_t *chardef = get_char_definition(fcfg, c); |
| paul@78 | 55 | uint8_t *imagerow = chardef->data, |
| paul@91 | 56 | *displayline = cfg->screen_start + y * cfg->line_length, |
| paul@78 | 57 | bitmap, mask; |
| paul@78 | 58 | |
| paul@78 | 59 | for (sy = 0, dy = y; (sy < chardef->height) && (dy < cfg->line_count); sy++, dy++) |
| paul@78 | 60 | { |
| paul@91 | 61 | if (displayline >= cfg->screen_limit) |
| paul@91 | 62 | displayline -= cfg->screen_size; |
| paul@91 | 63 | |
| paul@78 | 64 | bitmap = *imagerow; |
| paul@78 | 65 | |
| paul@78 | 66 | for (dx = x, mask = 1 << (chardef->width - 1); (mask) && (dx < cfg->line_length); dx++, mask >>= 1) |
| paul@78 | 67 | { |
| paul@78 | 68 | if (bitmap & mask) |
| paul@111 | 69 | displayline[display_get_position(cfg, dx)] = colour; |
| paul@78 | 70 | } |
| paul@78 | 71 | |
| paul@78 | 72 | imagerow += 1; |
| paul@78 | 73 | displayline += cfg->line_length; |
| paul@78 | 74 | } |
| paul@78 | 75 | |
| paul@78 | 76 | return x + chardef->width; |
| paul@78 | 77 | } |
| paul@132 | 78 | |
| paul@132 | 79 | /* Write a string to the screen, updating the coordinates to indicate the next |
| paul@132 | 80 | character position. */ |
| paul@132 | 81 | |
| paul@132 | 82 | void write_string(display_config_t *cfg, font_config_t *fcfg, const char *s, |
| paul@132 | 83 | int *x, int *y, uint8_t colour) |
| paul@132 | 84 | { |
| paul@132 | 85 | const int line_height = 9; |
| paul@132 | 86 | |
| paul@132 | 87 | while (*s) |
| paul@132 | 88 | { |
| paul@132 | 89 | if (*x + get_char_definition(fcfg, *s)->width > cfg->line_length) |
| paul@132 | 90 | { |
| paul@132 | 91 | *x = 0; *y += line_height; |
| paul@132 | 92 | } |
| paul@132 | 93 | |
| paul@132 | 94 | if (*y + line_height >= cfg->line_count) |
| paul@132 | 95 | break; |
| paul@132 | 96 | |
| paul@132 | 97 | *x = write_char(cfg, fcfg, *s, *x, *y, colour); |
| paul@132 | 98 | s++; |
| paul@132 | 99 | } |
| paul@132 | 100 | } |
