gint/src/render-cg/topti.c

127 lines
3.5 KiB
C

#include <gint/defs/types.h>
#include <gint/defs/attributes.h>
#include <gint/display.h>
#include <string.h>
#include "../render/render.h"
#include "topti-asm.h"
/* Default font */
extern font_t gint_font8x9;
font_t const * gint_default_font = &gint_font8x9;
font_t const * topti_font = &gint_font8x9;
/* topti_glyph(): Render a glyph on the VRAM
Prints a glyph naively using word accesses, because for most fonts with a
small size (including gint's 8x9 font) this will be more efficient than the
complex logic for longword accesses.
This function assumes that at least one of [fg] and [bg] is not transparent.
@vram Target position on VRAM, adjusted to [top], not adjusted to [left]
@data Glyph data
@left Left-position of subglyph
@top Top-Position of subglyph
@width Subglyph width
@height Subglyph height
@dataw Glyph width
@fg @bg Foreground and background colors */
static void topti_glyph(uint16_t *vram, uint32_t const * data, int left,
int top, int width, int height, int dataw, int fg, int bg)
{
int index = top * dataw + left;
/* Most common situation: opaque text on transparent background */
if(bg < 0) topti_glyph_fg(vram + left, data, fg, height, width,
dataw - width, index);
/* Full text on opaque background */
else if(fg >= 0) topti_glyph_fg_bg(vram + left, data, (fg << 16) | bg,
height, width, dataw - width, index);
/* Draw background but not text */
else topti_glyph_bg(vram + left, data, bg, height, width,
dataw - width, index);
}
static void topti_render(int x, int y, char const *str_char, font_t const *f,
int fg, int bg, int size)
{
uint8_t const *str = (void *)str_char;
uint8_t const *str0 = str;
/* Raw glyph data */
uint32_t const *data = f->data;
/* Storage height, top position within glyph */
int height = f->data_height, top = 0;
/* Vertical clipping */
if(x > 395 || y > 223 || y + height <= 0) return;
if(y + height > 224) height = 224 - y;
if(y < 0) top = -y, height += y, y = 0;
/* Move to top row */
uint16_t *target = gint_vram + 396 * y;
/* Character spacing waiting to be drawn, in pixels */
int space = 0;
/* Read each character from the input string */
while(1)
{
uint32_t code_point = topti_utf8_next(&str);
if(!code_point || (size >= 0 && str - str0 > size)) break;
int glyph = topti_glyph_index(f, code_point);
if(glyph < 0) continue;
int dataw = f->prop ? f->glyph_width[glyph] : f->width;
/* Draw character spacing if background is opaque */
if(space && bg >= 0) drect(x, y, x+space-1, y+height-1, bg);
x += space;
if(x >= 396) break;
int index = topti_offset(f, glyph);
/* Compute horizontal intersection between glyph and screen */
int width = dataw, left = 0;
if(x + dataw <= 0)
{
x += dataw;
space = f->char_spacing;
continue;
}
if(x < 0) left = -x, width += x;
if(x + width > 396) width = 396 - x;
/* Render glyph */
topti_glyph(target + x, data + index, left, top, width, height,
dataw, fg, bg);
x += dataw;
space = f->char_spacing;
}
}
/* dtext_opt(): Display a string of text */
void dtext_opt(int x, int y, int fg, int bg, int halign, int valign,
char const *str, int size)
{
if(halign != DTEXT_LEFT || valign != DTEXT_TOP)
{
int w, h;
dnsize(str, size, topti_font, &w, &h);
if(halign == DTEXT_RIGHT) x -= w - 1;
if(halign == DTEXT_CENTER) x -= (w >> 1);
if(valign == DTEXT_BOTTOM) y -= h - 1;
if(valign == DTEXT_MIDDLE) y -= (h >> 1);
}
topti_render(x, y, str, topti_font, fg, bg, size);
}