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Handle inversed text

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This commit is contained in:
Peter Evans 2018-01-24 20:05:47 -06:00
parent f36bba2e83
commit 217b27b040
1 changed files with 36 additions and 1 deletions
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37
src/apple2.text.c
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@ -10,12 +10,14 @@
* implemented as part of both fonts.
*/
#include <ctype.h>
#include "apple2.text.h"
void
apple2_text_draw(apple2 *mach, size_t addr)
{
int err;
int err, bit7, bit6;
vm_8bit ch;
vm_area dest;
vm_bitfont *font;
@ -38,12 +40,45 @@ apple2_text_draw(apple2 *mach, size_t addr)
// What are we working with?
ch = mos6502_get(mach->cpu, addr);
// Bit 7 and bit 6 mean different things in ALTCHAR
// and...non-ALTCHAR.
bit7 = ch & 0x80;
bit6 = ch & 0x40;
// The ASCII code we will use is only that which is composed of the
// first 6 bits.
ch = ch & 0x7f;
// We treat special characters as spaces for display purposes.
if (ch < 0x20) {
vm_bitfont_render(font, mach->screen, &dest, ' ');
return;
}
// If bit 7 is high, then we want to show inverse video. This is
// mostly true regardless of character set.
if (bit7) {
font = mach->invfont;
}
if (mach->display_mode & DISPLAY_ALTCHAR) {
// The character here should be MouseText, so we'll need to use
// the _non_ inverted font for that.
if (ch >= 0x40 && ch <= 0x5F) {
font = mach->sysfont;
}
if (bit6) {
ch = tolower(ch);
}
} else {
// FIXME: we should turn on flashing text here, but that's not
// yet implemented
if (bit6) {
// do something with flashing text
}
}
// Blank out the space on the screen, then show the character
vm_bitfont_render(font, mach->screen, &dest, ' ');
vm_bitfont_render(font, mach->screen, &dest, ch);