add basic terminal

include/term.h

@@ -0,0 +1,26 @@
+#ifndef _NVBOARD_TERM_H
+#define _NVBOARD_TERM_H
+
+class Term {
+private:
+  SDL_Renderer *renderer;
+  SDL_Rect region;
+  int w_in_char, h_in_char;
+  std::vector<uint8_t *> lines;
+  int cursor_x, cursor_y;
+  SDL_Texture *cursor_texture;
+  int screen_y;
+
+  void clear_screen();
+  uint8_t *new_line();
+  void draw_cursor();
+
+public:
+  Term(SDL_Renderer *r, int x, int y, int w, int h);
+  ~Term();
+  void feed_ch(uint8_t ch);
+  void update_gui();
+};
+
+#endif
+

include/uart.h

@@ -2,14 +2,13 @@
 #define _NVBOARD_UART_H
 
 #include <component.h>
-#include <string>
+#include <term.h>
 
 class UART : public Component{
 private:
-  int region_w, region_h;
-  std::string str;
+  Term *term;
 public:
-  UART(SDL_Renderer *rend, int cnt, int init_val, int ct);
+  UART(SDL_Renderer *rend, int cnt, int init_val, int ct, int x, int y, int w, int h);
   ~UART();
 
   virtual void update_gui();

src/font.cpp

@@ -1,29 +1,41 @@
 #include <nvboard.h>
 #include <SDL_ttf.h>
 
-static TTF_Font *font = NULL;
+static SDL_Texture* font[128] = { NULL };
 
-void init_font() {
+void init_font(SDL_Renderer *renderer) {
   int ret = TTF_Init();
   assert(ret != -1);
   std::string nvboard_home = getenv("NVBOARD_HOME");
-  font = TTF_OpenFont((nvboard_home + "/resources/font/" + "FreeMono.ttf").c_str(), 16);
-  assert(font != NULL);
+
+  TTF_Font *f = TTF_OpenFont((nvboard_home + "/resources/font/" + "FreeMono.ttf").c_str(), 16);
+  assert(f != NULL);
+  TTF_SetFontHinting(f, TTF_HINTING_MONO);
+  TTF_SetFontStyle(f, TTF_STYLE_BOLD);
+
+  SDL_Color c = {.r = 0x00, .g = 0x00, .b = 0x00 };
+  for (int i = 1; i < 128; i ++) {
+    SDL_Surface *s = TTF_RenderGlyph_Solid(f, i, c);
+    if (s == NULL) {
+      printf("error = %s\n", SDL_GetError());
+    }
+    assert(s != NULL);
+    assert(s->w == 10);
+    assert(s->h == 16);
+    SDL_Texture *t = SDL_CreateTextureFromSurface(renderer, s);
+    assert(t != NULL);
+    font[i] = t;
+    SDL_FreeSurface(s);
+  }
+
+  TTF_CloseFont(f);
 }
 
-SDL_Texture* render_str(SDL_Renderer *renderer, std::string str, int wrap_len_in_pixel, int *w, int *h) {
-  SDL_Color c = {.r = 0x00, .g = 0x00, .b = 0x00 };
-  SDL_Surface *s = TTF_RenderText_Solid_Wrapped(font, str.c_str(), c, wrap_len_in_pixel);
-  assert(s != NULL);
-  SDL_Texture *t = SDL_CreateTextureFromSurface(renderer, s);
-  assert(t != NULL);
-  *w = s->w; *h = s->h;
-  SDL_FreeSurface(s);
-  return t;
+SDL_Texture* get_font_texture(uint8_t ch) {
+  assert(ch < 128);
+  return font[ch == 0 ? ' ' : ch];
 }
 
 void close_font() {
-  TTF_CloseFont(font);
-  font = NULL;
   TTF_Quit();
 }

src/nvboard.cpp

@@ -79,9 +79,8 @@ void nvboard_init(int vga_clk_cycle) {
     );
     SDL_SetRenderDrawColor(main_renderer, 0xff, 0xff, 0xff, 0);
 
-    void init_font();
-    init_font();
-
+    void init_font(SDL_Renderer *renderer);
+    init_font(main_renderer);
     init_render(main_renderer);
     init_components(main_renderer);
     init_gui(main_renderer);

src/term.cpp

@@ -0,0 +1,78 @@
+#include <nvboard.h>
+#include <term.h>
+
+SDL_Texture* get_font_texture(uint8_t ch);
+
+Term::Term(SDL_Renderer *r, int x, int y, int w, int h):
+    renderer(r), cursor_x(0), cursor_y(0), screen_y(0) {
+  region = { .x = x, .y = y, .w = w, .h = h };
+  w_in_char = region.w / 10;
+  h_in_char = region.h / 16;
+  uint8_t *l = new_line();
+  memset(l, 'a', w_in_char);
+  cursor_texture = new_texture(r, 10, 16, 0x10, 0x10, 0x10);
+}
+
+Term::~Term() {
+  SDL_DestroyTexture(cursor_texture);
+}
+
+void Term::clear_screen() {
+  SDL_RenderFillRect(renderer, &region);
+}
+
+uint8_t* Term::new_line() {
+  uint8_t *l = new uint8_t[w_in_char];
+  memset(l, ' ', w_in_char);
+  lines.push_back(l);
+  return l;
+}
+
+void Term::feed_ch(uint8_t ch) {
+  assert(ch < 128);
+  int y = cursor_y;
+  assert(y < lines.size());
+  uint8_t *l = lines[y];
+  l[cursor_x] = ch;
+  cursor_x ++;
+  if (cursor_x == w_in_char) {
+    cursor_x = 0;
+    cursor_y ++;
+    if (cursor_y >= lines.size()) new_line();
+    if (cursor_y == screen_y + h_in_char) screen_y ++;  // scroll one line
+  }
+}
+
+void Term::draw_cursor() {
+  if (cursor_y >= screen_y && cursor_y < screen_y + h_in_char) {
+    int y = cursor_y - screen_y;
+    int x = cursor_x;
+    SDL_Rect rect = region;
+    rect.w = 10, rect.h = 16;
+    rect.y += 16 * y;
+    rect.x += 10 * x;
+    SDL_RenderCopy(renderer, cursor_texture, NULL, &rect);
+  }
+}
+
+void Term::update_gui() {
+  clear_screen();
+
+  SDL_Rect rect = region;
+  int x_start = rect.x;
+  rect.w = 10, rect.h = 16;
+  for (int y = 0; y < h_in_char; y ++) {
+    if (screen_y + y >= lines.size()) break;
+    uint8_t *l = lines[screen_y + y];
+    for (int x = 0; x < w_in_char; x ++) {
+      uint8_t ch = l[x];
+      SDL_Texture *t  = get_font_texture(ch);
+      SDL_RenderCopy(renderer, t, NULL, &rect);
+      rect.x += 10;
+    }
+    rect.x = x_start;
+    rect.y += 16;
+  }
+  draw_cursor();
+  set_redraw();
+}

src/uart.cpp

@@ -3,14 +3,9 @@
 
 UART* uart = NULL;
 
-SDL_Texture* render_str(SDL_Renderer *renderer, std::string str, int wrap_len_in_pixel, int *w, int *h);
-
-UART::UART(SDL_Renderer *rend, int cnt, int init_val, int ct):
-    Component(rend, cnt, init_val, ct),
-    region_w(WINDOW_WIDTH / 2), region_h(WINDOW_HEIGHT / 2), str(" ") {
-  SDL_Texture *temp_texture = SDL_CreateTexture(rend, SDL_PIXELFORMAT_ARGB8888,
-    SDL_TEXTUREACCESS_STREAMING, region_w, region_h);
-  set_texture(temp_texture, 0);
+UART::UART(SDL_Renderer *rend, int cnt, int init_val, int ct, int x, int y, int w, int h):
+    Component(rend, cnt, init_val, ct) {
+  term = new Term(rend, x, y, w, h);
 }
 
 UART::~UART() {
@@ -18,15 +13,7 @@ UART::~UART() {
 }
 
 void UART::update_gui() {
-  SDL_Renderer *r = get_renderer();
-  SDL_Rect rect = *get_rect(0);
-  SDL_RenderFillRect(r, &rect);
-  int w = 0, h = 0;
-  SDL_Texture *t = render_str(r, str, region_w, &w, &h);
-  rect.w = w; rect.h = h;
-  SDL_RenderCopy(r, t, NULL, &rect);
-  SDL_DestroyTexture(t);
-  set_redraw();
+  term->update_gui();
 }
 
 void UART::update_state() {
@@ -34,15 +21,18 @@ void UART::update_state() {
   i ++;
   if (i < 10) return;
   i = 0;
-  char last = str[str.length() - 1];
-  str += last + 1;
+  static uint8_t ch = ' ';
+  ch += 1;
+  if (ch == 128) ch = ' ';
+  term->feed_ch(ch);
   update_gui();
 }
 
 void init_uart(SDL_Renderer *renderer) {
-  uart = new UART(renderer, 1, 0, UART_TYPE);
+  int x = WINDOW_WIDTH / 2, y = 0, w = WINDOW_WIDTH / 2, h = WINDOW_HEIGHT / 2;
+  uart = new UART(renderer, 1, 0, UART_TYPE, x, y, w, h);
   SDL_Rect *rect_ptr = new SDL_Rect;
-  *rect_ptr = (SDL_Rect){WINDOW_WIDTH / 2, 0, WINDOW_WIDTH / 2, WINDOW_HEIGHT / 2};
+  *rect_ptr = (SDL_Rect){x, y, w, h};
   uart->set_rect(rect_ptr, 0);
   uart->add_pin(UART_TX);
   uart->add_pin(UART_RX);