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changed text attribute BLINKING to FLAGS, introduced flags for BLINKI…
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…NG and FONT_PAGE_A
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@chschnell
chschnell committed Sep 22, 2024
1 parent 6dec4bd commit 91efd19
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Showing 2 changed files with 35 additions and 91 deletions.
118 changes: 29 additions & 89 deletions src/browser/screen.js
View file
Original file line number Diff line number Diff line change
Expand Up @@ -84,11 +84,14 @@ function ScreenAdapter(options, screen_fill_buffer)
blink_visible;

const CHARACTER_INDEX = 0;
const BLINKING_INDEX = 1;
const FLAGS_INDEX = 1;
const BG_COLOR_INDEX = 2;
const FG_COLOR_INDEX = 3;
const TEXT_MODE_COMPONENT_SIZE = 4;

const FLAG_BLINKING = 0x01;
const FLAG_FONT_PAGE_A = 0x02;

var stopped = false;
var paused = false;

Expand Down Expand Up @@ -206,13 +209,13 @@ function ScreenAdapter(options, screen_fill_buffer)
return dst_bitmap;
}

function rebuild_graphical_text_buffer() // was: GraphicalText.rebuild_image_data()
function rebuild_graphical_text_buffer()
{
if(!font_width || !text_mode_width || !font_height || !text_mode_height)
if(!font_width || !font_height || !text_mode_width || !text_mode_height)
{
console.log(font_width, text_mode_width, font_height, text_mode_height);
return;
}
/*

const gfx_width = font_width * text_mode_width;
const gfx_height = font_height * text_mode_height;
const gfx_size = gfx_width * gfx_height * 4;
Expand All @@ -229,47 +232,20 @@ function ScreenAdapter(options, screen_fill_buffer)
changed_rows.fill(1);
}
// TODO: send bus message about changed screen size?
*/
}

function render_dirty_rows()
{
//const vga = this.vga; // deprecated
//const vga_memory = vga.vga_memory; // deprecated
//onst txt_width = this.txt_width; // use text_mode_width instead
//const txt_height = this.txt_height; // use text_mode_height instead
//const txt_row_dirty = this.txt_row_dirty; // use changed_rows instead
// const gfx_data = this.gfx_data; // use graphical_text_buffer instead
//const font_bitmap = this.font_bitmap; // ok
//const font_size = this.font_width * this.font_height;
//const font_A_offset = this.font_index_A * 256;
//const font_B_offset = this.font_index_B * 256;
const font_size = font_width * font_height;
const font_A_offset = font_page_a * 256;
const font_B_offset = font_page_b * 256;
const font_AB_enabled = font_A_offset !== font_B_offset;

//const font_blink_enabled = this.font_blink_enabled;
//const blink_visible = this.blink_visible; // ok
//const cursor_top = this.cursor_top; // use cursor_start instead
//const cursor_height = this.cursor_bottom - cursor_top + 1;
const font_blink_enabled = true; // TODO!
const cursor_visible = cursor_enabled && blink_visible;
const cursor_height = cursor_end - cursor_start + 1;

const gfx_width = font_width * text_mode_width;
const gfx_height = font_height * text_mode_height;

//const split_screen_row = vga.scan_line_to_screen_row(vga.line_compare);
//const bg_color_mask = font_blink_enabled ? 0x7 : 0xF;
//const palette = new Int32Array(16);
//for(let i = 0; i < 16; ++i)
//{
// palette[i] = vga.vga256_palette[vga.dac_mask & vga.dac_map[i]];
//}

//const txt_row_size = text_mode_width * 2;
//const txt_row_step = Math.max(0, (vga.offset_register * 2 - text_mode_width) * 2);
const txt_row_size = text_mode_width * TEXT_MODE_COMPONENT_SIZE;

// column size in graphical_text_buffer (tuple of 4 RGBA items)
Expand All @@ -292,16 +268,8 @@ function ScreenAdapter(options, screen_fill_buffer)
let draw_cursor, gfx_ic;
let row, col;

//txt_i = vga.start_address << 1;
for(row = 0, txt_i = 0; row < text_mode_height; ++row) //, txt_i += txt_row_step)
for(row = 0, txt_i = 0; row < text_mode_height; ++row)
{
/*
if(row === split_screen_row)
{
txt_i = 0;
}
*/

if(!changed_rows[row])
{
txt_i += txt_row_size;
Expand All @@ -310,21 +278,12 @@ function ScreenAdapter(options, screen_fill_buffer)

gfx_i = row * gfx_row_size;

//for(col = 0; col < text_mode_width; ++col, txt_i += 2, gfx_i += gfx_col_step)
for(col = 0; col < text_mode_width; ++col, txt_i += TEXT_MODE_COMPONENT_SIZE, gfx_i += gfx_col_step)
{
/*
chr = vga_memory[txt_i];
chr_attr = vga_memory[txt_i | 1];
chr_blinking = font_blink_enabled && chr_attr & 0x80;
chr_font_ofs = font_AB_enabled ? (chr_attr & 0x8 ? font_A_offset : font_B_offset) : font_A_offset;
chr_bg_rgba = palette[chr_attr >> 4 & bg_color_mask];
chr_fg_rgba = palette[chr_attr & 0xF];
*/
//const index = (y * text_mode_width + x) * TEXT_MODE_COMPONENT_SIZE;
const chr = text_mode_data[txt_i + CHARACTER_INDEX];
const chr_blinking = font_blink_enabled && text_mode_data[txt_i + BG_COLOR_INDEX];
const chr_font_ofs = font_AB_enabled ? font_A_offset : font_A_offset; // TODO! 4th bit of attribute byte selects font page A or B
const chr_flags = text_mode_data[txt_i + FLAGS_INDEX];
const chr_blinking = font_blink_enabled && chr_flags & FLAG_BLINKING;
const chr_font_ofs = font_AB_enabled ? (chr_flags & FLAG_FONT_PAGE_A ? font_A_offset : font_B_offset) : font_A_offset;
const chr_bg_rgba = text_mode_data[txt_i + BG_COLOR_INDEX];
const chr_fg_rgba = text_mode_data[txt_i + FG_COLOR_INDEX];

Expand Down Expand Up @@ -403,17 +362,14 @@ function ScreenAdapter(options, screen_fill_buffer)
// to avoid flickering during early startup
this.set_mode(is_graphical);

/*
if(!is_graphical)
*/
if(mode !== MODE_TEXT)
if(mode === MODE_TEXT)
{
// assume 80x25 with 9x16 font
this.set_size_graphical(720, 400, 720, 400);
this.set_size_text(80, 25);
}
else
{
this.set_size_text(80, 25);
// assume 80x25 with 9x16 font
this.set_size_graphical(720, 400, 720, 400);
}

this.timer();
Expand All @@ -423,9 +379,6 @@ function ScreenAdapter(options, screen_fill_buffer)
{
const image = new Image();

/*
if(is_graphical)
*/
if(mode !== MODE_TEXT)
{
image.src = graphic_screen.toDataURL("image/png");
Expand Down Expand Up @@ -475,18 +428,21 @@ function ScreenAdapter(options, screen_fill_buffer)
return image;
};

this.put_char = function(row, col, chr, blinking, bg_color, fg_color)
this.put_char = function(row, col, chr, flags, bg_color, fg_color)
{
if(!text_mode_data || !changed_rows || !text_mode_width || !text_mode_height)
{
return;
}

dbg_assert(row >= 0 && row < text_mode_height);
dbg_assert(col >= 0 && col < text_mode_width);
dbg_assert(chr >= 0 && chr < 0x100);

if(!text_mode_data || !changed_rows) { return; }

const p = TEXT_MODE_COMPONENT_SIZE * (row * text_mode_width + col);

text_mode_data[p + CHARACTER_INDEX] = chr;
text_mode_data[p + BLINKING_INDEX] = blinking;
text_mode_data[p + FLAGS_INDEX] = flags;
text_mode_data[p + BG_COLOR_INDEX] = bg_color;
text_mode_data[p + FG_COLOR_INDEX] = fg_color;

Expand All @@ -495,12 +451,6 @@ if(!text_mode_data || !changed_rows) { return; }

this.timer = function()
{
/*
if(!stopped)
{
requestAnimationFrame(() => is_graphical ? this.update_graphical() : this.update_text());
}
*/
if(!stopped)
{
switch(mode)
Expand Down Expand Up @@ -619,13 +569,12 @@ if(!text_mode_data || !changed_rows) { return; }

this.set_font_page = function(page_a, page_b)
{
if(!use_graphical_text || (font_page_a === page_a && font_page_b === page_b))
if(use_graphical_text && (font_page_a !== page_a || font_page_b !== page_b))
{
return;
font_page_a = page_a;
font_page_b = page_b;
changed_rows.fill(1);
}
font_page_a = page_a;
font_page_b = page_b;
// TODO: redraw
};

this.clear_screen = function()
Expand Down Expand Up @@ -698,12 +647,6 @@ if(!text_mode_data || !changed_rows) { return; }
graphic_context.imageSmoothingEnabled = false;

// add some scaling to tiny resolutions
/*
if(!options.disable_autoscale &&
width <= 640 &&
width * 2 < window.innerWidth * window.devicePixelRatio &&
height * 2 < window.innerHeight * window.devicePixelRatio)
*/
if(width <= 640 &&
width * 2 < window.innerWidth * window.devicePixelRatio &&
height * 2 < window.innerHeight * window.devicePixelRatio)
Expand Down Expand Up @@ -735,9 +678,6 @@ if(!text_mode_data || !changed_rows) { return; }

function update_scale_graphic()
{
/*
elem_set_scale(graphic_screen, scale_x * base_scale, scale_y * base_scale, false);
*/
if(!options.disable_autoscale)
{
elem_set_scale(graphic_screen, scale_x * base_scale, scale_y * base_scale, false);
Expand Down Expand Up @@ -860,7 +800,7 @@ if(!text_mode_data || !changed_rows) { return; }
{
color_element = document.createElement("span");

blinking = text_mode_data[offset + BLINKING_INDEX];
blinking = text_mode_data[offset + FLAGS_INDEX] & FLAG_BLINKING;
bg_color = text_mode_data[offset + BG_COLOR_INDEX];
fg_color = text_mode_data[offset + FG_COLOR_INDEX];

Expand All @@ -876,7 +816,7 @@ if(!text_mode_data || !changed_rows) { return; }

// put characters of the same color in one element
while(i < text_mode_width &&
text_mode_data[offset + BLINKING_INDEX] === blinking &&
text_mode_data[offset + FLAGS_INDEX] & FLAG_BLINKING === blinking &&
text_mode_data[offset + BG_COLOR_INDEX] === bg_color &&
text_mode_data[offset + FG_COLOR_INDEX] === fg_color)
{
Expand Down
8 changes: 6 additions & 2 deletions src/vga.js
View file
Original file line number Diff line number Diff line change
Expand Up @@ -846,10 +846,12 @@ VGAScreen.prototype.text_mode_redraw = function()
const chr = this.vga_memory[addr];
const color = this.vga_memory[addr | 1];
const blinking = blink_flag && (color & 1 << 7);
const font_page_a = color & 1 << 3;
const flags = (blinking ? 1 : 0) | (font_page_a ? 2 : 0);

this.bus.send("screen-put-char", [row, col, chr]);

this.screen.put_char(row, col, chr, blinking,
this.screen.put_char(row, col, chr, flags,
this.vga256_palette[this.dac_mask & this.dac_map[color >> 4 & bg_color_mask]],
this.vga256_palette[this.dac_mask & this.dac_map[color & 0xF]]);

Expand Down Expand Up @@ -904,11 +906,13 @@ VGAScreen.prototype.vga_memory_write_text_mode = function(addr, value)
}
const blink_flag = this.attribute_mode & 1 << 3;
const blinking = blink_flag && (color & 1 << 7);
const font_page_a = color & 1 << 3;
const flags = (blinking ? 1 : 0) | (font_page_a ? 2 : 0);
const bg_color_mask = blink_flag ? 7 : 0xF;

this.bus.send("screen-put-char", [row, col, chr]);

this.screen.put_char(row, col, chr, blinking,
this.screen.put_char(row, col, chr, flags,
this.vga256_palette[this.dac_mask & this.dac_map[color >> 4 & bg_color_mask]],
this.vga256_palette[this.dac_mask & this.dac_map[color & 0xF]]);
};
Expand Down

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