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#ifndef GBAEXP_TILES_H
#define GBAEXP_TILES_H
#include <stdarg.h>
#include <stdio.h>
#include "common.h"
#include "bitmap.h"
#include "posprintf.h"
#include "ppu.h"
typedef struct TextEngine {
// Currently working on tiled backgrounds only. The X and Y positions
// correspond to the tile X and Y starting from the top left of the screen.
// For a 240x160 screen, we have 30x20 tiles available.
size_t cursor_x;
size_t cursor_y;
// Pointer to the memory being used for writing to the screen.
u32 *memory;
// The font used to render the text.
u8 color;
} TextEngine;
static TextEngine text_engine = {0};
void
txt_putc(char c) {
if (c == '\0') {
return;
}
if (c == '\n') {
text_engine.cursor_x = 0;
text_engine.cursor_y++;
} else {
int x = text_engine.cursor_x;
int y = text_engine.cursor_y;
putfontchar(text_engine.memory, x, y, c, text_engine.color);
text_engine.cursor_x += 1;
if (text_engine.cursor_x >= 30) {
text_engine.cursor_x = 0;
text_engine.cursor_y++;
}
}
if (text_engine.cursor_y >= 20) {
text_engine.cursor_y = 0;
}
}
static inline void
txt_puts(char *msg) {
while (*msg) {
txt_putc(*msg++);
}
}
void
txt_init(u8 color, u32 *buf) {
// Prepare text engine.
text_engine.color = color;
text_engine.memory = buf;
}
// Print text to the screen with formatting.
#define txt_printf(msg, ...) \
{ \
char buf[256] = {0}; \
posprintf(buf, msg, ##__VA_ARGS__); \
txt_puts(buf); \
}
void
txt_clear_line(void) {
for (size_t i = 0; i < 30; ++i) {
int x = text_engine.cursor_x;
int y = text_engine.cursor_y;
putfontchar(text_engine.memory, x, y, ' ', text_engine.color);
}
text_engine.cursor_x = 0;
}
void
txt_clear_screen(void) {
for (size_t j = 0; j < 20; ++j) {
text_engine.cursor_y = j;
txt_clear_line();
}
text_engine.cursor_x = 0;
text_engine.cursor_y = 0;
}
void
txt_position(size_t tile_x, size_t tile_y) {
text_engine.cursor_x = tile_x;
text_engine.cursor_y = tile_y;
}
#endif // GBAEXP_TILES_H
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