From 4cdc29383a94497c0fe762833d6577d1c44944ae Mon Sep 17 00:00:00 2001
From: Alexey Ryabov <alex@b00bl1k.ru>
Date: Sun, 11 May 2025 00:18:05 +0500
Subject: [PATCH] Implement drawing and scrolling text in textview

---
 README.md                    |   2 +
 icons.png                    | Bin 445 -> 523 bytes
 kterm.asm                    |  69 ++++++++++----
 screenshot.png               | Bin 0 -> 3929 bytes
 textview.asm => textview.inc | 180 ++++++++++++++++++++++++++---------
 utils.asm => utils.inc       |   0
 6 files changed, 186 insertions(+), 65 deletions(-)
 create mode 100644 screenshot.png
 rename textview.asm => textview.inc (62%)
 rename utils.asm => utils.inc (100%)

diff --git a/README.md b/README.md
index b3c9e90..2f47a41 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,8 @@
 
 Simple serial terminal for KolibriOS.
 
+![screenshot](screenshot.png)
+
 # Requirements
 
 - [Fasm](https://flatassembler.net/) 1.7x
diff --git a/icons.png b/icons.png
index c1ba64d83b4790dfc38c35e365ed9c97f4a20500..b420b222643967128e8db0cf706a6fdfef8a7815 100644
GIT binary patch
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D30A-g

delta 330
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diff --git a/kterm.asm b/kterm.asm
index 1bea7a2..1395db6 100644
--- a/kterm.asm
+++ b/kterm.asm
@@ -33,7 +33,7 @@ BTN_SEND = 5
 BTN_OK = 2
 BTN_CANCEL = 3
 
-__DEBUG__ = 0
+__DEBUG__ = 1
 __DEBUG_LEVEL__ = 0
 
 include '../../proc32.inc'
@@ -43,8 +43,8 @@ include '../../dll.inc'
 include '../../debug-fdo.inc'
 include '../../develop/libraries/box_lib/trunk/box_lib.mac'
 include '../../../drivers/serial/common.inc'
-include 'textview.asm'
-include 'utils.asm'
+include 'textview.inc'
+include 'utils.inc'
 
 start:
         mcall   SF_SYS_MISC, SSF_HEAP_INIT
@@ -54,7 +54,7 @@ start:
         or      eax, eax
         jnz     .exit
 
-        mcall   SF_SET_EVENTS_MASK, EVM_MOUSE + EVM_MOUSE_FILTER + EVM_REDRAW + EVM_BUTTON + EVM_KEY
+        mcall   SF_SET_EVENTS_MASK, EVM_MOUSE + EVM_REDRAW + EVM_BUTTON + EVM_KEY
 
         mov     byte [ed_send_val], 0
         stdcall text_view_init, text_view
@@ -69,7 +69,16 @@ start:
         dec     eax
         jz      .btn
         invoke  edit_box_mouse, ed_send
+        push    [vscroll.position]
         invoke  scrollbar_mouse, vscroll
+        pop     eax
+        cmp     eax, [vscroll.position]
+        je      @f
+        mov     eax, [vscroll.position]
+        mov     [text_view.curr_line], eax
+        DEBUGF  0, "vscroll.position=%d\n", eax
+        stdcall text_view_draw, text_view
+  @@:
         jmp     .loop
     .win:
         call    .draw_window
@@ -93,7 +102,10 @@ start:
     @@:
         cmp     ah, BTN_CLEAR
         jne     @f
-        ; TODO
+        stdcall text_view_clear, text_view
+        stdcall text_view_draw, text_view
+        call    update_vscroll
+        invoke  scrollbar_draw, vscroll
         jmp     .loop
     @@:
         cmp     ah, BTN_SEND
@@ -134,6 +146,7 @@ start:
         mcall   SF_DEFINE_BUTTON, <59, 24>, <5, 24>, BTN_CLEAR, [sc.work_light]
 
         mcall   SF_PUT_IMAGE_EXT, icons, <20, 20>, <3, 7>, 1, icons.palette, 0
+        mcall   SF_PUT_IMAGE_EXT, icons + 180, <20, 20>, <61, 7>, 1, icons.palette, 0
 
         mov     ebx, icons + 60 ; disconnected icon
         mov     al, [is_connected]
@@ -180,6 +193,7 @@ start:
         sub     eax, 2 * FONT_HEIGHT + WIN_BORDER_WIDTH + 14 + SCROLL_TOP
         mov     [vscroll.y_size], ax
 
+        call    update_vscroll
         invoke  scrollbar_draw, vscroll
 
         ; editbox and send button
@@ -352,15 +366,29 @@ show_conn_window:
         mcall   SF_REDRAW, SSF_END_DRAW
         ret
 
-send_text:
-    stdcall text_view_append_line, text_view, ed_send_val
-    xor     eax, eax
-    push    eax
-    invoke  edit_box_set_text, ed_send, esp
-    pop     eax
-    stdcall text_view_draw, text_view
-    invoke  edit_box_draw, ed_send
-    ret
+
+proc send_text
+        stdcall text_view_append_line, text_view, ed_send_val
+        xor     eax, eax
+        push    eax
+        invoke  edit_box_set_text, ed_send, esp
+        pop     eax
+        stdcall text_view_draw, text_view
+        invoke  edit_box_draw, ed_send
+        call    update_vscroll
+        invoke  scrollbar_draw, vscroll
+        ret
+endp
+
+proc update_vscroll
+        mov     eax, [text_view.total_lines]
+        mov     [vscroll.max_area], eax
+        mov     eax, [text_view.rows]
+        mov     [vscroll.cur_area], eax
+        mov     eax, [text_view.curr_line]
+        mov     [vscroll.position], eax
+        ret
+endp
 
 align 16
 @IMPORT:
@@ -409,14 +437,14 @@ port_conf:
         db      8, 1, SERIAL_CONF_PARITY_NONE, SERIAL_CONF_FLOW_CTRL_NONE
 port_conf_end:
 
-if __DEBUG__ eq 1
+;if __DEBUG__ eq 1
     include_debug_strings
-end if
+;end if
 
 ; https://javl.github.io/image2cpp/
 icons:
-    ; 'icons', 20x60px
-    db 0xff, 0xff, 0xf0, 0xfc, 0xff, 0xf0, 0xf8, 0x3f, 0xf0, 0xf8, 0x1f, 0xf0, 0xfe, 0x1f, 0xf0, 0xdf
+    ; 'icons', 20x80px
+    db 0xff, 0xff, 0xf0, 0xfc, 0x7f, 0xf0, 0xf8, 0x3f, 0xf0, 0xf8, 0x1f, 0xf0, 0xfe, 0x1f, 0xf0, 0xdf
     db 0x1f, 0xf0, 0x8e, 0x1f, 0xf0, 0xa4, 0x3f, 0xf0, 0x90, 0x1f, 0xf0, 0xc8, 0x0f, 0xf0, 0xe0, 0x07
     db 0xf0, 0xfe, 0x43, 0xf0, 0xff, 0x21, 0xf0, 0xff, 0x90, 0xf0, 0xff, 0xc8, 0x70, 0xff, 0xe4, 0x30
     db 0xff, 0xf0, 0x70, 0xff, 0xf8, 0xf0, 0xff, 0xfd, 0xf0, 0xff, 0xff, 0xf0, 0xff, 0xff, 0xf0, 0xff
@@ -427,7 +455,10 @@ icons:
     db 0xf0, 0xff, 0xff, 0xf0, 0xff, 0x9f, 0xf0, 0xff, 0x0f, 0xf0, 0xfe, 0x07, 0xf0, 0xfe, 0x07, 0xf0
     db 0xfc, 0x03, 0xf0, 0x80, 0x00, 0x10, 0x80, 0x00, 0x10, 0xfc, 0x03, 0xf0, 0xfe, 0x07, 0xf0, 0xfe
     db 0x07, 0xf0, 0xff, 0x0f, 0xf0, 0xff, 0x9f, 0xf0, 0xff, 0xff, 0xf0, 0xff, 0xff, 0xf0, 0xff, 0xff
-    db 0xf0, 0xff, 0xff, 0xf0
+    db 0xf0, 0xff, 0xff, 0xf0, 0xff, 0xff, 0xf0, 0xff, 0xff, 0xf0, 0xff, 0xff, 0xf0, 0xff, 0xe3, 0xf0
+    db 0xff, 0xc9, 0xf0, 0xff, 0x9c, 0xf0, 0xff, 0x3e, 0x70, 0xfe, 0x7f, 0x70, 0xfc, 0x7f, 0x70, 0xf9
+    db 0x3e, 0x70, 0xf3, 0x9c, 0xf0, 0xe7, 0xc9, 0xf0, 0xef, 0xe3, 0xf0, 0xe7, 0xe7, 0xf0, 0xf3, 0xcf
+    db 0xf0, 0xf9, 0x9f, 0xf0, 0xfc, 0x00, 0x70, 0xff, 0xff, 0xf0, 0xff, 0xff, 0xf0, 0xff, 0xff, 0xf0
 .palette:
     dd 0xffffff
     dd 0x000000
diff --git a/screenshot.png b/screenshot.png
new file mode 100644
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GIT binary patch
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literal 0
HcmV?d00001

diff --git a/textview.asm b/textview.inc
similarity index 62%
rename from textview.asm
rename to textview.inc
index f4759bb..ceaadaa 100644
--- a/textview.asm
+++ b/textview.inc
@@ -1,4 +1,5 @@
 BUF_SIZE = 4096
+FRM_WIDTH = 1
 MARGIN = 1
 
 struct  TEXT_VIEW
@@ -16,7 +17,7 @@ struct  TEXT_VIEW
 
         total_lines dd ?
         curr_line   dd ?
-        max_length  dd ?
+        max_length  dd ? ; length of the longest string
 
         rows        dd ?
         cols        dd ?
@@ -45,59 +46,40 @@ proc text_view_deinit stdcall uses ebx, text_view:dword
 endp
 
 proc text_view_draw stdcall uses ebx esi edi, text_view:dword
-        ; draw frame and background
         mov     esi, [text_view]
+        call    tv.draw_frame_and_bg
+        call    tv.calc_rows_and_cols
+        DEBUGF  0, "text_view rows=%d cols=%d\n", [esi + TEXT_VIEW.rows], [esi + TEXT_VIEW.cols]
+
+        mov     eax, [esi + TEXT_VIEW.curr_line]
+        mov     ebx, [esi + TEXT_VIEW.total_lines]
+        DEBUGF  0, "text_view curr_line=%d total_lines=%d\n", eax, ebx
+        sub     ebx, eax
+        cmp     ebx, [esi + TEXT_VIEW.rows]
+        jbe     @f
+        mov     ebx, [esi + TEXT_VIEW.rows]
+    @@:
+        mov     edi, [esi + TEXT_VIEW.buf_data]
+        call    goto_curr_line
+        mov     ecx, ebx ; ecx = count lines
+        xor     eax, eax ; eax = index from 0
+
         mov     ebx, [esi + TEXT_VIEW.left]
-        shl     ebx, 16
-        add     ebx, [esi + TEXT_VIEW.width]
-        mov     ecx, [esi + TEXT_VIEW.top]
-        shl     ecx, 16
-        add     ecx, [esi + TEXT_VIEW.height]
-        mov     edx, [esi + TEXT_VIEW.fg_color]
-        call    draw_frame
-        add     ebx, 1 shl 16
-        sub     ebx, 2
-        add     ecx, 1 shl 16
-        sub     ecx, 2
-        mov     edx, [esi + TEXT_VIEW.bg_color]
-        mcall   SF_DRAW_RECT
-        ; calc rows and cols
-        mov     eax, [esi + TEXT_VIEW.width]
-        sub     eax, MARGIN * 2
-        shr     eax, 3 ; assume that font width is 8 px
-        mov     [esi + TEXT_VIEW.cols], eax
-        xor     edx, edx
-        mov     eax, [esi + TEXT_VIEW.height]
-        sub     eax, MARGIN * 2
-        mov     ebx, FONT_HEIGHT + MARGIN * 2
-        div     ebx
-        mov     [esi + TEXT_VIEW.rows], eax
-        ; draw lines
-        xor     eax, eax ; rows
-        mov     ebx, [esi + TEXT_VIEW.left]
-        add     ebx, MARGIN + 1 ; frame width
+        add     ebx, MARGIN + FRM_WIDTH
         shl     ebx, 16
         add     ebx, [esi + TEXT_VIEW.top]
-        add     ebx, MARGIN + 1 ; frame width
-        mov     edi, [esi + TEXT_VIEW.buf_data]
+        add     ebx, MARGIN + FRM_WIDTH
+
     .draw_lines:
-        cmp     eax, [esi + TEXT_VIEW.total_lines]
+        cmp     eax, ecx
         jae     .draw_lines_end
-        mov     ecx, 0x90000000
-        or      ecx, [esi + TEXT_VIEW.fg_color]
-        mov     edx, edi
-        push    eax
-        mcall   SF_DRAW_TEXT
+        push    eax ecx
+        call    tv.draw_single_line
         ; move edi pointer to the next string
-        push    esi
-        mov     esi, edi
-        call    strlen
         add     edi, eax
         inc     edi
-        pop     esi
-        ; next line num
-        pop     eax
-        inc     eax
+        pop     ecx eax
+        inc     eax ; next line num
         add     ebx, FONT_HEIGHT + MARGIN
         jmp     .draw_lines
     .draw_lines_end:
@@ -143,7 +125,112 @@ proc text_view_append_line stdcall uses ebx esi edi, text_view:dword, string:dwo
         ret
 endp
 
-draw_frame:
+proc text_view_clear stdcall uses ebx, text_view:dword
+        mov     edx, [text_view]
+        mov     ecx, [edx + TEXT_VIEW.buf_data]
+        test    ecx, ecx
+        jz      @f
+        mcall   SF_SYS_MISC, SSF_MEM_FREE
+    @@:
+        xor     eax, eax
+        mov     [edx + TEXT_VIEW.buf_data], eax
+        mov     [edx + TEXT_VIEW.buf_size], eax
+        mov     [edx + TEXT_VIEW.data_size], eax
+        mov     [edx + TEXT_VIEW.total_lines], eax
+        mov     [edx + TEXT_VIEW.curr_line], eax
+        mov     [edx + TEXT_VIEW.max_length], eax
+        ret
+endp
+
+proc text_view_deinit stdcall uses ebx, text_view:dword
+        mov     edx, [text_view]
+        mov     ecx, [edx + TEXT_VIEW.buf_data]
+        test    ecx, ecx
+        jz      @f
+        mcall   SF_SYS_MISC, SSF_MEM_FREE
+    @@:
+        ret
+endp
+
+proc tv.draw_frame_and_bg
+; esi = text_view
+        mov     ebx, [esi + TEXT_VIEW.left]
+        shl     ebx, 16
+        add     ebx, [esi + TEXT_VIEW.width]
+        mov     ecx, [esi + TEXT_VIEW.top]
+        shl     ecx, 16
+        add     ecx, [esi + TEXT_VIEW.height]
+        mov     edx, [esi + TEXT_VIEW.fg_color]
+        call    draw_frame
+        add     ebx, 1 shl 16
+        sub     ebx, 2
+        add     ecx, 1 shl 16
+        sub     ecx, 2
+        mov     edx, [esi + TEXT_VIEW.bg_color]
+        mcall   SF_DRAW_RECT
+        ret
+endp
+
+proc tv.calc_rows_and_cols
+; esi = text_view
+        mov     eax, [esi + TEXT_VIEW.width]
+        sub     eax, (FRM_WIDTH + MARGIN) * 2
+        shr     eax, 3 ; assume that font width is 8 px
+        mov     [esi + TEXT_VIEW.cols], eax
+        xor     edx, edx
+        mov     eax, [esi + TEXT_VIEW.height]
+        sub     eax, MARGIN * 2
+        mov     ebx, FONT_HEIGHT + MARGIN
+        div     ebx
+        mov     [esi + TEXT_VIEW.rows], eax
+        ret
+endp
+
+proc tv.draw_single_line uses esi
+; esi = text_view
+; ebx = coordinates: left << 16 + top
+; edi = pointer to the first byte of string in [text_view.buf_data]
+; return: eax = length of the string
+        mov     ecx, 0x10000000 ; fixed-length string
+        or      ecx, [esi + TEXT_VIEW.fg_color]
+        push    esi
+        mov     esi, edi
+        call    strlen
+        pop     esi
+        push    eax
+        cmp     eax, [esi + TEXT_VIEW.cols]
+        jbe     .len_ok
+        mov     eax, [esi + TEXT_VIEW.cols]
+    .len_ok:
+        mov     esi, eax
+        mov     edx, edi
+        mcall   SF_DRAW_TEXT
+        pop     eax
+        ret
+endp
+
+proc goto_curr_line uses ebx esi
+; eax = curr line index
+; edi = buf
+        mov     ebx, eax
+        xor     ecx, ecx
+        mov     esi, edi
+        cld
+    .scan:
+        cmp     ecx, ebx
+        je      .exit
+        lodsb
+        test    al, al
+        jnz     .scan
+        inc     ecx
+        jmp     .scan
+    .exit:
+        mov     eax, ebx
+        mov     edi, esi
+        ret
+endp
+
+proc draw_frame
 ; ebx = left << 16 + width
 ; ecx = top << 16 + height
 ; edx = color
@@ -180,3 +267,4 @@ draw_frame:
         mcall   SF_DRAW_LINE
         pop     ecx ebx
         ret
+endp
diff --git a/utils.asm b/utils.inc
similarity index 100%
rename from utils.asm
rename to utils.inc