Speech bubbles

game/game.c

@@ -29,10 +29,17 @@ void game_update() {
     sys_update();
 
     game_frame += 1;
+
+    bool allow_input = true;
+
+    if (sys_btn(DEVICE_BUTTON_2)) {
+        game_dialogue_display("Hello, world!\nYou rock.");
+    }
+
     game_collectibles_update();
     game_npcs_update();
-    game_player_update();
-
+    game_dialogue_update(&allow_input);
+    game_player_update(&allow_input);
 }
 
 void game_draw() {
@@ -46,4 +53,6 @@ void game_draw() {
     game_player_draw();
 
     sys_camera_reset();
+
+    game_dialogue_draw();
 }

game/game.h

@@ -3,6 +3,7 @@
 
 #include "game_collectible.h"
 #include "game_collision.h"
+#include "game_dialogue.h"
 #include "game_math.h"
 #include "game_npc.h"
 #include "game_palette.h"

game/game_dialogue.c

@@ -0,0 +1,138 @@
+#include <assert.h>
+#include <stdbool.h>
+#include "device/device.h"
+#include "game.h"
+
+#define GAME_DIALOGUE_MAX_N_CHARS 256
+
+typedef enum {
+    GAME_DIALOGUE_SCREEN_STATE_BOB_IN,
+    GAME_DIALOGUE_SCREEN_STATE_TYPEWRITER,
+    GAME_DIALOGUE_SCREEN_STATE_WAIT,
+    GAME_DIALOGUE_SCREEN_STATE_BOB_OUT,
+} game_dialogue_screen_state;
+
+struct {
+    bool visible;
+    const char* dialogue;
+
+    sys_i32 w; 
+    sys_i32 h;
+
+    game_dialogue_screen_state state;
+    sys_i32 state_progress;
+    sys_i32 n_chars_shown;
+    sys_i32 n_chars;
+} game_dialogue_screen;
+
+uint8_t game_dialogue_frame;
+
+void game_dialogue_display(const char* text) {
+    game_dialogue_screen.visible = true;
+    game_dialogue_screen.dialogue = text;
+    sys_measure_text(text, &game_dialogue_screen.w, &game_dialogue_screen.h);
+
+    game_dialogue_screen.state = GAME_DIALOGUE_SCREEN_STATE_BOB_IN;
+    game_dialogue_screen.state_progress = 0;
+    game_dialogue_screen.n_chars_shown = 0;
+    game_dialogue_screen.n_chars = strlen(text);
+    assert(game_dialogue_screen.n_chars <= GAME_DIALOGUE_MAX_N_CHARS);
+}
+
+void game_dialogue_update(bool* allow_input) {
+    game_dialogue_frame = ((uint32_t) game_dialogue_frame + 1) & 0xff;
+
+    if (
+        game_dialogue_screen.visible && 
+        game_dialogue_screen.state < GAME_DIALOGUE_SCREEN_STATE_BOB_OUT
+    ) { 
+        *allow_input = false;
+
+        if (sys_btnp(DEVICE_BUTTON_0, false)) {
+            if (game_dialogue_screen.state < GAME_DIALOGUE_SCREEN_STATE_WAIT) {
+                game_dialogue_screen.state = GAME_DIALOGUE_SCREEN_STATE_WAIT;
+                game_dialogue_screen.n_chars_shown = game_dialogue_screen.n_chars;
+            } else {
+                game_dialogue_screen.state = GAME_DIALOGUE_SCREEN_STATE_BOB_OUT;
+                game_dialogue_screen.state_progress = 0;
+            }
+        }
+    }
+
+    switch (game_dialogue_screen.state) {
+    case GAME_DIALOGUE_SCREEN_STATE_BOB_IN:
+        game_dialogue_screen.state_progress += 25;
+        if (game_dialogue_screen.state_progress >= 0x100) {
+            game_dialogue_screen.state = GAME_DIALOGUE_SCREEN_STATE_TYPEWRITER;
+            game_dialogue_screen.state_progress = 0;
+        }
+        break;
+    case GAME_DIALOGUE_SCREEN_STATE_TYPEWRITER: 
+        if (game_dialogue_frame % 4 == 0) {
+            game_dialogue_screen.n_chars_shown = sys_min_i32(
+                game_dialogue_screen.n_chars_shown + 1,
+                game_dialogue_screen.n_chars
+            );
+        }
+        if (game_dialogue_screen.n_chars_shown >= game_dialogue_screen.n_chars) {
+            game_dialogue_screen.state = GAME_DIALOGUE_SCREEN_STATE_WAIT;
+        }
+        break;
+    case GAME_DIALOGUE_SCREEN_STATE_WAIT:
+        break;
+    case GAME_DIALOGUE_SCREEN_STATE_BOB_OUT:
+        game_dialogue_screen.state_progress += 25;
+        if (game_dialogue_screen.state_progress >= 0x100) {
+            game_dialogue_screen.visible = false;
+            game_dialogue_screen.state_progress = 0;
+        }
+    }
+}
+void game_dialogue_draw() {
+    if (!game_dialogue_screen.visible) { return; }
+
+    sys_i32 x = DEVICE_W / 2 - game_dialogue_screen.w / 2;
+    sys_i32 y = DEVICE_H - game_dialogue_screen.h - 8;
+
+    sys_i32 cx = DEVICE_W / 2;
+    sys_i32 cy = DEVICE_H - game_dialogue_screen.h / 2 - 8;
+
+    sys_i32 interp_amt = 0;
+    switch (game_dialogue_screen.state) {
+        case GAME_DIALOGUE_SCREEN_STATE_BOB_IN:
+            interp_amt = 255 - game_dialogue_screen.state_progress;
+            break;
+        case GAME_DIALOGUE_SCREEN_STATE_BOB_OUT:
+            interp_amt = game_dialogue_screen.state_progress;
+            break;
+        default:
+            break;
+    }
+
+    int x0 = x - 4;
+    int y0 = y - 4;
+    int x1 = x + game_dialogue_screen.w + 4;
+    int y1 = y + game_dialogue_screen.h + 4;
+
+    sys_oval_fill(
+        x0 + (cx - x0) * interp_amt / 256,
+        y0 + (cy - y0) * interp_amt / 256,
+        x1 + (cx - x1) * interp_amt / 256,
+        y1 + (cy - y1) * interp_amt / 256,
+        1
+    );
+
+    if (game_dialogue_screen.state == GAME_DIALOGUE_SCREEN_STATE_BOB_OUT) {
+        return;
+    }
+    char chars[GAME_DIALOGUE_MAX_N_CHARS + 1];
+    strcpy(chars, game_dialogue_screen.dialogue);
+    chars[game_dialogue_screen.n_chars_shown] = 0;
+
+    for (int dy = -1; dy <= 1; dy++) {
+        for (int dx = -1; dx <= 1; dx++) {
+            sys_print(chars, x+dx, y+dy, 0);
+        }
+    }
+    sys_print(chars, x, y, 7);
+}

game/game_dialogue.h

@@ -0,0 +1,11 @@
+#ifndef GAME_DIALOGUE_H
+#define GAME_DIALOGUE_H
+
+#include <stdbool.h>
+
+void game_dialogue_display(const char* text);
+
+void game_dialogue_update(bool* allow_input);
+void game_dialogue_draw();
+
+#endif // GAME_DIALOGUE_H

game/game_player.c

@@ -37,7 +37,7 @@ void game_player_init() {
     game_player_bbox.y = game_map_player_start_y;
 }
 
-void game_player_update() {
+void game_player_update(bool* allow_input) {
     game_collision collision = game_collision_move_to_contact(
         &game_player_bbox, 
         game_player_dx, 
@@ -63,8 +63,8 @@ void game_player_update() {
         }
 
         int wanted_dx = game_player_dx;
-        if (sys_btn(DEVICE_BUTTON_L)) { wanted_dx -= 0x50; }
-        if (sys_btn(DEVICE_BUTTON_R)) { wanted_dx += 0x50; }
+        if (*allow_input && sys_btn(DEVICE_BUTTON_L)) { wanted_dx -= 0x50; }
+        if (*allow_input && sys_btn(DEVICE_BUTTON_R)) { wanted_dx += 0x50; }
     
         // allow this if grounded or if it's not a change of direction
         if (
@@ -82,7 +82,7 @@ void game_player_update() {
     }
 
     if (game_player_grounded || game_player_coyote_frames > 0) {
-        if (sys_btnp(DEVICE_BUTTON_U, false)) { 
+        if (*allow_input && sys_btnp(DEVICE_BUTTON_U, false)) { 
             game_player_dy = -0x200; 
             game_player_jump_frames = 13;
             game_player_grounded = false;

game/game_player.h

@@ -2,7 +2,7 @@
 #define GAME_PLAYER_H
 
 void game_player_init();
-void game_player_update();
+void game_player_update(bool* allow_input);
 void game_player_set_camera();
 void game_player_draw();
 

sys/sys_graphics.c

@@ -57,7 +57,26 @@ sys_color sys_pixel_get(sys_i32 x, sys_i32 y) {
     return device_pixels[y][x];
 }
 
-void sys_print(char* str, sys_i32 x, sys_i32 y, sys_color col) {
+void sys_measure_text(const char* str, sys_i32* w, sys_i32* h) {
+    sys_i32 x = 0;
+    sys_i32 y = 0;
+
+    sys_i32 max_x = 0;
+
+    for (sys_i32 i = 0;; i++) {
+        max_x = sys_max_i32(x, max_x);
+        uint8_t c = str[i];
+        if (c == 0) { break; }
+        if (c == '\n') { x = 0; y += 8; continue; }
+        if (c == '\r') { x = 0; continue; }
+        x += 8;
+    }
+
+    *w = max_x;
+    *h = y + 8;
+}
+
+void sys_print(const char* str, sys_i32 x, sys_i32 y, sys_color col) {
     x += sys_cam_dx;
     y += sys_cam_dy;
 

sys/sys_graphics.h

@@ -54,10 +54,16 @@ sys_color sys_pixel_get(
 
 // TODO: SSET/SGET
 // TODO: FGET/FSET
+
+/**
+ * Output the dimensions of the text (x and y)
+*/
+void sys_measure_text(const char* str, sys_i32* x, sys_i32* y);
+
 /**
  * Print a string `str` in the color `col`
  */
-void sys_print(char* str, sys_i32 x, sys_i32 y, sys_color col);
+void sys_print(const char* str, sys_i32 x, sys_i32 y, sys_color col);
 // TODO: CURSOR? COLOR?
 
 /**