gameplay: add block breaking

src/game.cpp

@@ -36,3 +36,35 @@ bool Game::moveCursorBy(WorldCoord dir)
     this->cursorPos = this->world->limits.clampPoint(candidatePos);
     return true;
 }
+
+int Game::blockBreakingDuration() const
+{
+    BlockInfo *info = this->world->blockInfoAt(this->cursorPos);
+    if(!info)
+        return -1;
+
+    /* Determine how many ticks would be needed with the current tool */
+    // TODO: Query the user's current tool
+    int requiredTicks = info->baseBreakDurationTicks;
+    return requiredTicks;
+}
+
+int8_t Game::blockBreakingProgress() const
+{
+    return this->damageTicks * 4 / this->blockBreakingDuration();
+}
+
+void Game::updateBlockBreaking()
+{
+    if(this->damageTicks < 0)
+        return;
+    this->damageTicks++;
+
+    int requiredTicks = this->blockBreakingDuration();
+
+    if(this->damageTicks >= requiredTicks) {
+        this->world->trySetCellAt(this->cursorPos.x, this->cursorPos.y,
+            BlockID(AIR));
+        this->damageTicks = -1;
+    }
+}

src/game.h

@@ -9,11 +9,27 @@ struct Game
     World *world;
     Camera *camera;
 
+    /* Current player/cursor positions (they are linked) */
     WorldCoord playerPos;
     WorldCoord cursorPos;
 
+    /* Current ticks spent damaging the pointed block, ≥ 0 when breaking */
+    int damageTicks;
+
+    bool isBreakingBlock() const {
+        return this->damageTicks >= 0;
+    }
+    /* Time required to break currently selected block */
+    int blockBreakingDuration() const;
+    /* Block breaking progress as a range 0-3 */
+    int8_t blockBreakingProgress() const;
+
     /* Move the player by specified amount. */
     bool movePlayerBy(WorldCoord dir, bool camera_follow=true);
     /* Move the cursor by the specified amount. */
     bool moveCursorBy(WorldCoord dir);
+
+    // --== Tick update functions ==--
+
+    void updateBlockBreaking();
 };

src/main.cpp

@@ -57,6 +57,15 @@ static void renderGame(Game *game)
 	GlyphCluster playerCluster(GLYPH_DEGREE_UNDERLINE, ' ',
 		GLYPH_CAPITAL_LAMBDA, ' ');
 	GlyphCluster cursorCluster(0, GLYPH_OPLUS, 0, 0);
+
+	if(game->isBreakingBlock()) {
+		static Glyph breakingGlyphs[4] = {
+			GLYPH_MIDDLE_DOT, GLYPH_SMALL_SQUARE, GLYPH_CURRENCY_SIGN, 0x7f,
+		};
+		int stage = game->blockBreakingProgress();
+		cursorCluster.glyphs[1] = breakingGlyphs[stage];
+	}
+
 	Nooncraft::renderCamera(26, 12, camera, game->playerPos, playerCluster,
 		game->cursorPos, cursorCluster);
 
@@ -105,6 +114,7 @@ int main(void)
 	game.playerPos = world->findSpawnPoint();
 	// TODO: Potential world border overflow here (unlikely)
 	game.cursorPos = game.playerPos + WorldCoord::Right;
+	game.damageTicks = -1;
 
 	volatile int nextFrame = 1;
 	int t = timer_configure(TIMER_ANY, 1000000/20, GINT_CALL_SET(&nextFrame));
@@ -129,17 +139,26 @@ int main(void)
 
 		key_event_t ev;
 		while((ev = pollevent()).type != KEYEV_NONE) {
-			if(ev.type == KEYEV_UP)
+			if(ev.type == KEYEV_UP) {
+				if(ev.key == KEY_OPTN) {
+					game.damageTicks = -1;
+					continue;
+				}
 				continue;
+			}
 			if(getkey_global_shortcuts(ev))
 				continue;
 
 			if(ev.key == KEY_MENU)
 				runMainLoop = false;
+			if(ev.key == KEY_OPTN) {
+				if(game.world->canBreakBlock(game.cursorPos))
+					game.damageTicks = 0;
+			}
 		}
 
 		/* Clamp speed to 10 blocks/s */
-		if(tick % 2 == 0) {
+		if(tick % 2 == 0 && !game.isBreakingBlock()) {
 			if(keydown(KEY_LEFT) && !keydown(KEY_SHIFT))
 				game.movePlayerBy(WorldCoord::Left);
 			if(keydown(KEY_RIGHT) && !keydown(KEY_SHIFT))
@@ -158,6 +177,8 @@ int main(void)
 			if(keydown(KEY_DOWN) && keydown(KEY_SHIFT))
 				game.moveCursorBy(WorldCoord::Down);
 		}
+
+		game.updateBlockBreaking();
 	}
 
 	timer_stop(t);

src/world.cpp

@@ -213,6 +213,20 @@ WorldCoord World::findSpawnPoint()
     return WorldCoord(0, 0);
 }
 
+BlockInfo *World::blockInfoAt(WorldCoord p) const
+{
+    if(!this->limits.contains(p))
+        return nullptr;
+    return Nooncraft::getBlockInfo(this->cellAt(p.x, p.y));
+}
+
+bool World::canBreakBlock(WorldCoord p) const
+{
+    BlockInfo *info = blockInfoAt(p);
+    return info && info->breakability != Breakability::Fluid
+                && info->breakability != Breakability::Unbreakable;
+}
+
 namespace Nooncraft {
 
 World *mkWorld(int width, int height)

src/world.h

@@ -121,6 +121,10 @@ struct World
 
     bool validSpawn(int x, int y) const;
     WorldCoord findSpawnPoint();
+
+    BlockInfo *blockInfoAt(WorldCoord p) const;
+
+    bool canBreakBlock(WorldCoord p) const;
 };
 
 namespace Nooncraft {