restructure code and add simple collision detection

Makefile

@@ -10,6 +10,10 @@ CTAGS_CMD = $(CTAGS_PATH) -auef
 TAGS_FILE = TAGS
 
 all:
+	$(ARDUINO) --verify tetris.ino
+
+
+upload:
 	$(ARDUINO) --upload tetris.ino
 
 

tetris.ino

@@ -2,42 +2,53 @@
 #include <TFT_eSPI.h>
 #include <SPI.h>
 
-TFT_eSPI tft = TFT_eSPI();       // Invoke custom library
+// We assume the size of the screen 120x160
-// pins are defined un User_Setup.h
+#define GRID_WIDTH   12
+#define GRID_HEIGHT  16
+#define BLOCK_SIZE   10
+#define BLOCK_MARGIN  2
 
 const int BTN1_PIN = 25;
 volatile bool btn1_pressed = false;
 const int BTN2_PIN = 33;
 volatile bool btn2_pressed = false;
 
+// I am using ST7735S, a very cheap display from aliexpress
+TFT_eSPI tft = TFT_eSPI();
+// pins are defined un User_Setup.h
+
+
 // forward declarations
 void IRAM_ATTR isr1();
 void IRAM_ATTR isr2();
 
-void setup() {
+// the main board and the offboard, to check for dirty squares
-  tft.init();   // initialize a ST7735S chip
-
-  // set up the buttons and the interrupts
-  pinMode(BTN1_PIN, INPUT_PULLUP);
-  attachInterrupt(BTN1_PIN, isr1, FALLING);
-  pinMode(BTN2_PIN, INPUT_PULLUP);
-  attachInterrupt(BTN2_PIN, isr2, FALLING);
-
-  init_board();
-
-  delay(100);
-}
-
-#define GRID_WIDTH   12
-#define GRID_HEIGHT  18
-#define BLOCK_SIZE   10
-#define BLOCK_MARGIN  2
-
-#define BLOCK_WIDTH    20
-#define BLOCK_HEIGHT   30
-
 uint32_t main_board[GRID_WIDTH][GRID_HEIGHT], offboard[GRID_WIDTH][GRID_HEIGHT];
+/* 
+   The value (i,j) on the board is given by main_board[i][j].
+   if board(i,j) = 0, then the space there is empty
+   otherwise board(i,j)'s first bit determines whether the block is "old" or not, and the rest denotes a color
+ */
 
+
+/* Blocks are defined in grids of 4x4:
+
+  0    1   2   3
+  4    5   6   7
+  8    9  10  11
+  12  13  14  15
+
+*/
+#define BLOCKS_COUNT 2
+uint8_t blocks[BLOCKS_COUNT][4] =
+  {
+   {0,1,2,3},{0,1,4,5}
+  };
+
+#define COLORS_SIZE  6
+uint32_t block_colors[COLORS_SIZE] = { TFT_NAVY, TFT_DARKGREEN, TFT_RED, TFT_YELLOW, TFT_GREEN, TFT_PINK };
+
+// Graphics-related functions
 void
 init_board()
 {
@@ -51,6 +62,17 @@ init_board()
       }
 }
 
+void
+set_board(int i, int j, int color, bool old)
+{
+ int v = color<<1;
+ if (old)
+   {
+     v = v|1;
+   }
+ main_board[i][j] = v;
+}
+
 void
 draw_board()
 {
@@ -59,43 +81,108 @@ draw_board()
       {
         if (main_board[i][j] == offboard[i][j]) continue; // no need to redraw
         offboard[i][j] = main_board[i][j];
+        int color = main_board[i][j]>>1;
         tft.fillRect(i*BLOCK_SIZE+BLOCK_MARGIN,j*BLOCK_SIZE+BLOCK_MARGIN,
                      BLOCK_SIZE-BLOCK_MARGIN,BLOCK_SIZE-BLOCK_MARGIN,
-                     main_board[i][j]);
+                     color);
       }
 }
 
-uint8_t blocks[2][4] =
-  {
-   {0,1,2,3},{0,1,4,5}
-  };
-
-
 // Draw a block of type TYPE with color COLOR, starting at coordinates X, Y.
 // Updates the main_board directly
 void
-draw_block(int x, int y, int type, int color)
+draw_block(int x, int y, int type, int color, bool old)
 {
   for (int i = 0; i < 4; i++)
     {
       int v = blocks[type][i];
       int dx = v%4;
       int dy = v/4;
-      main_board[x+dx][y+dy] = color;
+      set_board(x+dx, y+dy, color, old);
     }
 }
 
+
+// Game logic
+
+// Current and previous positions of the active block
 int px = 0, cx = 0;
 int py = 0, cy = 0;
+// Type of the active block. Should be 0 <= cblokc_ty < BLOCKS_COUNT
 int cblock_ty = 0;
-void loop() {
+// Color of the current block
-  // if (dy == 0) {
+int cblock_color = TFT_RED;
-  //   dx = map(esp_random(), 0, 0xFFFFFFFF, 0, 128/5);
+
-  // }
+void
-  cy++;
+new_block()
-  if (cy >= GRID_HEIGHT) {
+{
-    cy = 0;
+  px = 0; cx = 0;
+  py = 0; cy = 0;
+  cblock_ty = 0;
+  cblock_color = TFT_RED;
+}
+
+bool
+check_collision()
+{
+  for (int i = 0; i < 4; i++)
+    {
+      int v = blocks[cblock_ty][i];
+      int dx = v%4;
+      int dy = v/4;
+      if (cy+dy >= GRID_HEIGHT)
+        {
+          return true;
         }
+      int is_old = main_board[cx+dx][cy+dy]&1;
+      if (is_old)
+        {
+          return true;
+        }
+    }
+
+  return false;
+}
+
+// Setup
+void setup() {
+  tft.init();   // initialize a ST7735S chip
+
+  Serial.begin(115200);
+
+  // set up the buttons and the interrupts
+  pinMode(BTN1_PIN, INPUT_PULLUP);
+  attachInterrupt(BTN1_PIN, isr1, FALLING);
+  pinMode(BTN2_PIN, INPUT_PULLUP);
+  attachInterrupt(BTN2_PIN, isr2, FALLING);
+
+  init_board();
+  new_block();
+
+  delay(100);
+}
+
+void loop() {
+
+  if (check_collision ())
+    {
+      // designate the block as "old" and leave it there
+      draw_block(px, py, cblock_ty, cblock_color, true);
+      new_block();
+      return;
+    }
+
+  // clear the previous block
+  if (cy != py || cx != px)
+    {
+      draw_block(px, py, cblock_ty, TFT_BLACK, false);
+    }
+  draw_block(cx, cy, cblock_ty, cblock_color, false);
+
+  draw_board();
+
+  px = cx;
+  py = cy;
 
   if (btn1_pressed)
     {
@@ -108,19 +195,9 @@ void loop() {
       cx++;
     }
 
-  // clear the previous block
+  cy++;
-  if (cy != py || cx != px)
-    {
-      draw_block(px, py, cblock_ty, TFT_BLACK);
-    }
-  draw_block(cx, cy, cblock_ty, TFT_RED);
-
-  draw_board();
 
   delay(350);
-
-  px = cx;
-  py = cy;
 }
 
 void IRAM_ATTR