tetris: factor out LockPiece()

src/tetris/clear.h

@@ -0,0 +1,14 @@
+// returns true iff the specified row of the board is clear (full with no gaps)
+bool LineClear(int y){
+  int dimx = board_->get_dim_x();
+  for(int x = 1 ; x < dimx - 1 ; ++x){
+    ncpp::Cell c;
+    if(board_->get_at(y, x, &c) < 0){
+      throw TetrisNotcursesErr("get_at()");
+    }
+    if(!c.get().gcluster || c.get().gcluster == ' '){
+      return false;
+    }
+  }
+  return true;
+}

src/tetris/lock.h

@@ -0,0 +1,35 @@
+void LockPiece(){
+  curpiece_->mergedown(*board_);
+  if(!board_->cursor_move(0, 1)){
+    throw TetrisNotcursesErr("cursor_move()");
+  }
+  int bdimy, bdimx;
+  board_->get_dim(&bdimy, &bdimx);
+  int cleared; // how many contiguous lines were cleared
+  do{
+    uint64_t tl, tr, bl, br;
+    tl = tr = bl = br = 0;
+    channels_set_bg_alpha(&tl, CELL_ALPHA_TRANSPARENT);
+    channels_set_bg_alpha(&tr, CELL_ALPHA_TRANSPARENT);
+    channels_set_bg_alpha(&bl, CELL_ALPHA_TRANSPARENT);
+    channels_set_bg_alpha(&br, CELL_ALPHA_TRANSPARENT);
+    channels_set_fg(&tl, 0xff0000);
+    channels_set_fg(&tr, 0x00ff00);
+    channels_set_fg(&bl, 0x0000ff);
+    channels_set_fg(&br, 0x00ffff);
+    if(!board_->stain(bdimy - 2, bdimx - 2, tl, tr, bl, br)){
+      throw TetrisNotcursesErr("stain()");
+    }
+    cleared = 0;
+    for(int y = bdimy - 2 ; y > 0 ; --y){
+      if(LineClear(y)){
+        ++cleared;
+      }else if(cleared){
+        break;
+      }
+    }
+    if(cleared){
+      // FIXME purge them, augment score
+    }
+  }while(cleared);
+}

src/tetris/main.cpp

@@ -46,6 +46,8 @@ public:
 
 #include "gravity.h"
 #include "ticker.h"
+#include "clear.h"
+#include "lock.h"
 #include "movedown.h"
 #include "moveleft.h"
 #include "moveright.h"

src/tetris/movedown.h

@@ -7,25 +7,7 @@ bool MoveDown() {
       if(y <= board_top_y_ - 1){
         return true;
       }
-      curpiece_->mergedown(*board_);
-      if(!board_->cursor_move(0, 1)){
-        throw TetrisNotcursesErr("cursor_move()");
-      }
-      int bdimy, bdimx;
-      board_->get_dim(&bdimy, &bdimx);
-      uint64_t tl, tr, bl, br;
-      tl = tr = bl = br = 0;
-      channels_set_bg_alpha(&tl, CELL_ALPHA_TRANSPARENT);
-      channels_set_bg_alpha(&tr, CELL_ALPHA_TRANSPARENT);
-      channels_set_bg_alpha(&bl, CELL_ALPHA_TRANSPARENT);
-      channels_set_bg_alpha(&br, CELL_ALPHA_TRANSPARENT);
-      channels_set_fg(&tl, 0xff0000);
-      channels_set_fg(&tr, 0x00ff00);
-      channels_set_fg(&bl, 0x0000ff);
-      channels_set_fg(&br, 0x00ffff);
-      if(!board_->stain(bdimy - 2, bdimx - 2, tl, tr, bl, br)){
-        throw TetrisNotcursesErr("stain()");
-      }
+      LockPiece();
       curpiece_ = NewPiece();
     }else{
       ++y;