ncplane_translate() accept NULL dest as standard plane #408 (#411)

* tetris man page
* tetris basic skeleton
* tetris: Ticker()
* README: fix up some obsolete terminology
* tetris: draw the game board
* tetris: add NewPiece()
* tetris: draw tetriminos
* tetris: check for stuck piece, move it down
* Accept NULL dst in ncplane_translate() #408

CMakeLists.txt

@@ -448,6 +448,27 @@ target_compile_definitions(notcurses-ncreel
     FORTIFY_SOURCE=2
 )
 
+file(GLOB TETRISSRC CONFIGURE_DEPENDS src/tetris/*.cpp)
+add_executable(notcurses-tetris ${TETRISSRC})
+target_include_directories(notcurses-tetris
+  PRIVATE
+    include
+    "${PROJECT_BINARY_DIR}/include"
+)
+target_link_libraries(notcurses-tetris
+  PRIVATE
+    Threads::Threads
+    notcurses++
+)
+target_compile_options(notcurses-tetris
+  PRIVATE
+    -Wall -Wextra -W -Wshadow ${DEBUG_OPTIONS}
+)
+target_compile_definitions(notcurses-tetris
+  PRIVATE
+    FORTIFY_SOURCE=2
+)
+
 # notcurses-view
 file(GLOB VIEWSRCS CONFIGURE_DEPENDS src/view/*.cpp)
 if(${USE_FFMPEG})
@@ -682,6 +703,7 @@ install(TARGETS notcurses-demo DESTINATION bin)
 install(TARGETS notcurses-input DESTINATION bin)
 install(TARGETS notcurses-ncreel DESTINATION bin)
 install(TARGETS notcurses-tester DESTINATION bin)
+install(TARGETS notcurses-tetris DESTINATION bin)
 if(${USE_FFMPEG})
 install(TARGETS notcurses-view DESTINATION bin)
 endif()

doc/man/index.html

@@ -22,6 +22,7 @@
   <a href="notcurses-ncreel.1.html">notcurses-ncreel</a>—experiments with ncreels<br/>
   <a href="notcurses-pydemo.1.html">notcurses-pydemo</a>—validates the Python wrappers<br/>
   <a href="notcurses-tester.1.html">notcurses-tester</a>—unit test driver<br/>
+  <a href="notcurses-tetris.1.html">notcurses-tetris</a>—Tetris in the terminal<br/>
   <a href="notcurses-view.1.html">notcurses-view</a>—renders images and video to the terminal<br/>
   <h2>C library (section 3)</h2>
   <a href="notcurses_cell.3.html">notcurses_cell</a>—operations on <tt>cell</tt> objects<br/>

doc/man/man1/notcurses-tetris.1.md

@@ -0,0 +1,32 @@
+% notcurses-tetris(1)
+% nick black <nickblack@linux.com>
+% v1.2.3
+
+# NAME
+
+notcurses-tetris - Render images and video to the console
+
+# SYNOPSIS
+
+**notcurses-tetris** [**-h|--help**] [**-l loglevel**]
+
+# DESCRIPTION
+
+**notcurses-tetris** implements Tetris using notcurses.
+
+# OPTIONS
+
+**-h**: Show help and exit.
+
+**-l loglevel**: Log everything (high log level) or nothing (log level 0) to stderr.
+
+# NOTES
+
+Optimal display requires a terminal advertising the **rgb** terminfo(5)
+capability, or that the environment variable **COLORTERM** is defined to
+**24bit** (and that the terminal honors this variable), along with a
+fixed-width font with good coverage of the Unicode Block Drawing Characters.
+
+# SEE ALSO
+
+**notcurses(3)**

doc/man/man3/notcurses_ncplane.3.md

@@ -151,6 +151,14 @@ It is an error for two threads to concurrently access a single ncplane. So long
 as rendering is not taking place, however, multiple threads may safely output
 to multiple ncplanes.
 
+**ncplane_translate** translates coordinates expressed relative to the plane
+**src**, and writes the coordinates of that cell relative to **dst**. The cell
+need not intersect with **dst**, though this will yield coordinates which are
+invalid for writing or reading on **dst**. If **dst** is **NULL**, it is taken
+to refer to the standard plane. **ncplane_translate_abs** takes coordinates
+expressed relative to the standard plane, and returns coordinates relative to
+**dst**, returning **false** if the coordinates are invalid for **dst**.
+
 **ncplane_mergedown** writes to **dst** the frame that would be rendered if only
 **src** and **dst** existed on the z-axis, ad **dst** represented the entirety
 of the rendering region. Only those cells where **src** intersects with **dst**

include/ncpp/Cell.hh

@@ -121,7 +121,7 @@ namespace ncpp
 			return cell_simple_p (&_cell);
 		}
 
-		uint32_t get_edc_idx () const noexcept
+		uint32_t get_egc_idx () const noexcept
 		{
 			return cell_egc_idx (&_cell);
 		}

include/ncpp/Plane.hh

@@ -118,6 +118,14 @@ namespace ncpp
 			return ncplane_pulse (plane, ts, fader, curry) != -1;
 		}
 
+    bool mergedown (Plane* dst = nullptr) {
+      return ncplane_mergedown(*this, dst ? dst->plane : nullptr);
+    }
+
+    bool mergedown (Plane& dst) {
+      return mergedown(&dst);
+    }
+
 		bool gradient (const char* egc, uint32_t attrword, uint64_t ul, uint64_t ur, uint64_t ll, uint64_t lr, int ystop, int xstop) const noexcept
 		{
 			return ncplane_gradient (plane, egc, attrword, ul, ur, ll, lr, ystop, xstop) != -1;
@@ -860,9 +868,7 @@ namespace ncpp
 
 		void translate (const Plane *dst, int *y = nullptr, int *x = nullptr) const
 		{
-			if (dst == nullptr)
+      ncplane_translate(*this, dst ? dst->plane: nullptr, y, x);
-				throw invalid_argument ("'dst' must be a valid pointer");
-			translate (*this, *dst, y, x);
 		}
 
 		void translate (const Plane &dst, int *y = nullptr, int *x = nullptr) noexcept
@@ -875,10 +881,7 @@ namespace ncpp
 			if (src == nullptr)
 				throw invalid_argument ("'src' must be a valid pointer");
 
-			if (dst == nullptr)
+      ncplane_translate(*src, dst ? dst->plane : nullptr, y, x);
-				throw invalid_argument ("'dst' must be a valid pointer");
-
-			translate (*src, *dst, y, x);
 		}
 
 		static void translate (const Plane &src, const Plane &dst, int *y = nullptr, int *x = nullptr) noexcept

include/notcurses/notcurses.h

@@ -410,7 +410,7 @@ API struct ncplane* ncplane_dup(struct ncplane* n, void* opaque);
 
 // provided a coordinate relative to the origin of 'src', map it to the same
 // absolute coordinate relative to thte origin of 'dst'. either or both of 'y'
-// and 'x' may be NULL.
+// and 'x' may be NULL. if 'dst' is NULL, it is taken to be the standard plane.
 API void ncplane_translate(const struct ncplane* src, const struct ncplane* dst,
                            int* RESTRICT y, int* RESTRICT x);
 

src/lib/fill.c

@@ -434,7 +434,7 @@ rotate_output(ncplane* dst, uint32_t tchan, uint32_t bchan){
 //
 // Ideally, rotation through 360 degrees will restore the original 2x1 squre.
 // Unfortunately, the case where a half block occupies a cell having the same
-// fore- and background will see it roated into a single full block. In
+// fore- and background will see it rotated into a single full block. In
 // addition, lower blocks eventually become upper blocks with their channels
 // reversed. In general:
 //

src/lib/internal.h

@@ -26,7 +26,6 @@
 #include <signal.h>
 #include <wctype.h>
 #include <stdbool.h>
-#include <pthread.h>
 #include "notcurses/notcurses.h"
 #include "egcpool.h"
 

src/lib/notcurses.c

@@ -1952,6 +1952,9 @@ bool ncplane_translate_abs(const ncplane* n, int* restrict y, int* restrict x){
 
 void ncplane_translate(const ncplane* src, const ncplane* dst,
                        int* restrict y, int* restrict x){
+  if(dst == NULL){
+    dst = ncplane_stdplane_const(src);
+  }
   if(y){
     *y = src->absy - dst->absy + *y;
   }

src/lib/render.c

@@ -382,6 +382,9 @@ postpaint(cell* fb, cell* lastframe, int dimy, int dimx,
 // paint within the real viewport currently.
 int ncplane_mergedown(ncplane* restrict src, ncplane* restrict dst){
   notcurses* nc = src->nc;
+  if(dst == NULL){
+    dst = nc->stdscr;
+  }
   int dimy, dimx;
   ncplane_dim_yx(dst, &dimy, &dimx);
   cell* fb = malloc(sizeof(*fb) * dimy * dimx);

src/tetris/main.cpp

@@ -0,0 +1,189 @@
+#include <iostream>
+#include <mutex>
+#include <thread>
+#include <chrono>
+#include <cstdlib>
+#include <clocale>
+#include <ncpp/NotCurses.hh>
+
+using namespace std::chrono_literals;
+
+// "North-facing" tetrimino forms (the form in which they are released from the
+// top) are expressed in terms of two rows having between two and four columns.
+// We map each game column to four columns and each game row to two rows.
+// Each byte of the texture maps to one 4x4 component block (and wastes 7 bits).
+static const struct tetrimino {
+  unsigned color;
+  const char* texture;
+} tetriminos[] = { // OITLJSZ
+  { 0xcbc900, "****"},   { 0x009caa, "    ****"}, { 0x952d98, " * ***"},
+  { 0xcf7900, "  ****"}, { 0x0065bd, "*  ***"},   { 0x69be28, " **** "},
+  { 0xbd2939, "**  **"} };
+
+class TetrisNotcursesErr : public std::runtime_error {
+public:
+  TetrisNotcursesErr(char const* const message) throw()
+    : std::runtime_error(message) {
+  }
+
+  virtual char const* what() const throw(){
+    return exception::what();
+  }
+};
+
+class Tetris {
+public:
+  Tetris(ncpp::NotCurses& nc) :
+    nc_(nc),
+    score_(0),
+    msdelay_(10ms),
+    curpiece_(nullptr),
+    stdplane_(nc_.get_stdplane())
+  {
+    curpiece_ = NewPiece();
+    DrawBoard();
+  }
+
+  // 0.5 cell aspect: One board height == one row. One board width == two columns.
+  static constexpr auto BOARD_WIDTH = 10;
+  static constexpr auto BOARD_HEIGHT = 20;
+
+  // FIXME ideally this would be called from constructor :/
+  void Ticker(){
+    std::chrono::milliseconds ms;
+    mtx_.lock();
+    do{
+      ms = msdelay_;
+      // FIXME loop and verify we didn't get a spurious wakeup
+      mtx_.unlock();
+      std::this_thread::sleep_for(ms);
+      mtx_.lock();
+      if(curpiece_){
+        int y, x;
+        curpiece_->get_yx(&y, &x);
+        ++y;
+        if(PieceStuck()){
+          // FIXME lock it into place, get next piece
+        }else{
+          if(!curpiece_->move(y, x) || !nc_.render()){
+            // FIXME
+          }
+        }
+      }
+    }while(ms != std::chrono::milliseconds::zero());
+  }
+
+  void Stop(){
+    mtx_.lock();
+    msdelay_ = std::chrono::milliseconds::zero(); // FIXME wake it up?
+    mtx_.unlock();
+  }
+
+private:
+  ncpp::NotCurses& nc_;
+  uint64_t score_;
+  std::mutex mtx_;
+  std::chrono::milliseconds msdelay_;
+  std::unique_ptr<ncpp::Plane> curpiece_;
+  ncpp::Plane* stdplane_;
+
+  void DrawBoard(){
+    int y, x;
+    stdplane_->get_dim(&y, &x);
+    uint64_t channels = 0;
+    channels_set_fg(&channels, 0x00b040);
+    if(!stdplane_->cursor_move(y - (BOARD_HEIGHT + 2), x / 2 - (BOARD_WIDTH + 1))){
+      throw TetrisNotcursesErr("cursor_move()");
+    }
+    if(!stdplane_->rounded_box(0, channels, y - 1, x / 2 + BOARD_WIDTH + 1, NCBOXMASK_TOP)){
+      throw TetrisNotcursesErr("rounded_box()");
+    }
+    if(!nc_.render()){
+      throw TetrisNotcursesErr("render()");
+    }
+  }
+
+  bool PieceStuck(){
+    if(!curpiece_){
+      return false;
+    }
+    // check for impact. iterate over bottom row of piece's plane, checking for
+    // presence of glyph. if there, check row below. if row below is occupied,
+    // we're stuck.
+    int y, x;
+    curpiece_->get_dim(&y, &x);
+    --y;
+    while(x--){
+      int cmpy = y + 1, cmpx = x; // need absolute coordinates via translation
+      curpiece_->translate(nullptr, &cmpy, &cmpx);
+      ncpp::Cell c;
+      auto egc = nc_.get_at(cmpy, cmpx, c);
+      if(!egc){
+        return false; // FIXME is this not indicative of an error?
+      }
+      if(*egc && *egc != ' '){
+        return true;
+      }
+    }
+    return false;
+  }
+
+  // tidx is an index into tetriminos. yoff and xoff are relative to the
+  // terminal's origin. returns colored north-facing tetrimino on a plane.
+  std::unique_ptr<ncpp::Plane> NewPiece(){
+    const int tidx = random() % 7;
+    const struct tetrimino* t = &tetriminos[tidx];
+    const size_t cols = strlen(t->texture);
+    int y, x;
+    stdplane_->get_dim(&y, &x);
+    const int xoff = x / 2 - BOARD_WIDTH + (random() % BOARD_WIDTH - 3);
+    const int yoff = y - (BOARD_HEIGHT + 4);
+    std::unique_ptr<ncpp::Plane> n = std::make_unique<ncpp::Plane>(2, cols, yoff, xoff, nullptr);
+    if(n){
+      uint64_t channels = 0;
+      channels_set_bg_alpha(&channels, CELL_ALPHA_TRANSPARENT);
+      channels_set_fg_alpha(&channels, CELL_ALPHA_TRANSPARENT);
+      n->set_fg(t->color);
+      n->set_base(channels, 0, "");
+      y = 0;
+      for(size_t i = 0 ; i < strlen(t->texture) ; ++i){
+        if(t->texture[i] == '*'){
+          if(n->putstr(y, x, "██") < 0){
+            return NULL;
+          }
+        }
+        y += ((x = ((x + 2) % cols)) == 0);
+      }
+    }
+    return n;
+  }
+
+};
+
+int main(void){
+  if(setlocale(LC_ALL, "") == nullptr){
+    return EXIT_FAILURE;
+  }
+  notcurses_options ncopts{};
+  ncpp::NotCurses nc(ncopts);
+  Tetris t{nc};
+  std::thread tid(&Tetris::Ticker, &t);
+  char32_t input;
+  ncinput ni;
+  while((input = nc.getc(true, &ni)) != (char32_t)-1){
+    if(input == 'q'){
+      break;
+    }
+    switch(input){
+      case NCKEY_LEFT: break;
+      case NCKEY_RIGHT: break;
+    }
+  }
+  if(input == 'q'){
+    t.Stop();
+    tid.join();
+  }else{
+    return EXIT_FAILURE;
+  }
+  return nc.stop() ? EXIT_SUCCESS : EXIT_FAILURE;
+}