Remove platform-dependent type Fl_Bitmask (not in documented public API).

2 files changed, 84 insertions, 12 deletions

diff --git a/src/drivers/GDI/Fl_GDI_Graphics_Driver.H b/src/drivers/GDI/Fl_GDI_Graphics_Driver.H
index 0749ab798..c916fc65e 100644
--- a/src/drivers/GDI/Fl_GDI_Graphics_Driver.H
+++ b/src/drivers/GDI/Fl_GDI_Graphics_Driver.H
@@ -69,8 +69,9 @@ public:
   virtual void *gc() {return gc_;}
 
   // --- bitmap stuff
-  Fl_Bitmask create_bitmask(int w, int h, const uchar *array);
-  void delete_bitmask(Fl_Bitmask bm);
+  HBITMAP create_bitmask(int w, int h, const uchar *array); // NOT virtual
+  virtual void delete_bitmask(fl_uintptr_t bm);
+  HBITMAP create_alphamask(int w, int h, int d, int ld, const uchar *array);
   virtual void draw_unscaled(const char* str, int n, int x, int y);
   virtual void draw_unscaled(int angle, const char *str, int n, int x, int y);
   virtual void rtl_draw_unscaled(const char* str, int n, int x, int y);
diff --git a/src/drivers/GDI/Fl_GDI_Graphics_Driver_image.cxx b/src/drivers/GDI/Fl_GDI_Graphics_Driver_image.cxx
index e10466088..4cfc745c9 100644
--- a/src/drivers/GDI/Fl_GDI_Graphics_Driver_image.cxx
+++ b/src/drivers/GDI/Fl_GDI_Graphics_Driver_image.cxx
@@ -334,11 +334,11 @@ void Fl_GDI_Graphics_Driver::colored_rectf(int x, int y, int w, int h, uchar r,
 }
 #endif
 
-// 'fl_create_bitmask()' - Create an N-bit bitmap for masking...
-Fl_Bitmask Fl_GDI_Graphics_Driver::create_bitmask(int w, int h, const uchar *data) {
+// Create an N-bit bitmap for masking...
+HBITMAP Fl_GDI_Graphics_Driver::create_bitmask(int w, int h, const uchar *data) {
   // this won't work when the user changes display mode during run or
   // has two screens with differnet depths
-  Fl_Bitmask bm;
+  HBITMAP bm;
   static uchar hiNibble[16] =
   { 0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
     0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0 };
@@ -393,7 +393,7 @@ Fl_Bitmask Fl_GDI_Graphics_Driver::create_bitmask(int w, int h, const uchar *dat
   return bm;
 }
 
-void Fl_GDI_Graphics_Driver::delete_bitmask(Fl_Bitmask bm) {
+void Fl_GDI_Graphics_Driver::delete_bitmask(fl_uintptr_t bm) {
   DeleteObject((HGDIOBJ)bm);
 }
 
@@ -476,6 +476,78 @@ void Fl_GDI_Printer_Graphics_Driver::draw_bitmap(Fl_Bitmap *bm, int XP, int YP,
 }
 
 
+// Create a 1-bit mask used for alpha blending
+HBITMAP Fl_GDI_Graphics_Driver::create_alphamask(int w, int h, int d, int ld, const uchar *array) {
+  HBITMAP bm;
+  int bmw = (w + 7) / 8;
+  uchar *bitmap = new uchar[bmw * h];
+  uchar *bitptr, bit;
+  const uchar *dataptr;
+  int x, y;
+  static uchar dither[16][16] = { // Simple 16x16 Floyd dither
+    { 0,   128, 32,  160, 8,   136, 40,  168,
+      2,   130, 34,  162, 10,  138, 42,  170 },
+    { 192, 64,  224, 96,  200, 72,  232, 104,
+      194, 66,  226, 98,  202, 74,  234, 106 },
+    { 48,  176, 16,  144, 56,  184, 24,  152,
+      50,  178, 18,  146, 58,  186, 26,  154 },
+    { 240, 112, 208, 80,  248, 120, 216, 88,
+      242, 114, 210, 82,  250, 122, 218, 90 },
+    { 12,  140, 44,  172, 4,   132, 36,  164,
+      14,  142, 46,  174, 6,   134, 38,  166 },
+    { 204, 76,  236, 108, 196, 68,  228, 100,
+      206, 78,  238, 110, 198, 70,  230, 102 },
+    { 60,  188, 28,  156, 52,  180, 20,  148,
+      62,  190, 30,  158, 54,  182, 22,  150 },
+    { 252, 124, 220, 92,  244, 116, 212, 84,
+      254, 126, 222, 94,  246, 118, 214, 86 },
+    { 3,   131, 35,  163, 11,  139, 43,  171,
+      1,   129, 33,  161, 9,   137, 41,  169 },
+    { 195, 67,  227, 99,  203, 75,  235, 107,
+      193, 65,  225, 97,  201, 73,  233, 105 },
+    { 51,  179, 19,  147, 59,  187, 27,  155,
+      49,  177, 17,  145, 57,  185, 25,  153 },
+    { 243, 115, 211, 83,  251, 123, 219, 91,
+      241, 113, 209, 81,  249, 121, 217, 89 },
+    { 15,  143, 47,  175, 7,   135, 39,  167,
+      13,  141, 45,  173, 5,   133, 37,  165 },
+    { 207, 79,  239, 111, 199, 71,  231, 103,
+      205, 77,  237, 109, 197, 69,  229, 101 },
+    { 63,  191, 31,  159, 55,  183, 23,  151,
+      61,  189, 29,  157, 53,  181, 21,  149 },
+    { 254, 127, 223, 95,  247, 119, 215, 87,
+      253, 125, 221, 93,  245, 117, 213, 85 }
+  };
+
+  // Generate a 1-bit "screen door" alpha mask; not always pretty, but
+  // definitely fast...  In the future we may be able to support things
+  // like the RENDER extension in XFree86, when available, to provide
+  // true RGBA-blended rendering.  See:
+  //
+  //     http://www.xfree86.org/~keithp/render/protocol.html
+  //
+  // for more info on XRender...
+  //
+  memset(bitmap, 0, bmw * h);
+
+  for (dataptr = array + d - 1, y = 0; y < h; y ++, dataptr += ld)
+    for (bitptr = bitmap + y * bmw, bit = 1, x = 0; x < w; x ++, dataptr += d) {
+      if (*dataptr > dither[x & 15][y & 15])
+        *bitptr |= bit;
+      if (bit < 128) bit <<= 1;
+      else {
+        bit = 1;
+        bitptr ++;
+      }
+    }
+
+  bm = create_bitmask(w, h, bitmap);
+  delete[] bitmap;
+
+  return bm;
+}
+
+
 void Fl_GDI_Graphics_Driver::cache(Fl_RGB_Image *img)
 {
   Fl_Image_Surface *surface = new Fl_Image_Surface(img->data_w(), img->data_h());
@@ -485,7 +557,7 @@ void Fl_GDI_Graphics_Driver::cache(Fl_RGB_Image *img)
   } else {
     fl_draw_image(img->array, 0, 0, img->data_w(), img->data_h(), img->d(), img->ld());
     if (img->d() == 2 || img->d() == 4) {
-      *Fl_Graphics_Driver::mask(img) = (fl_uintptr_t)fl_create_alphamask(img->data_w(), img->data_h(), img->d(), img->ld(), img->array);
+      *Fl_Graphics_Driver::mask(img) = (fl_uintptr_t)create_alphamask(img->data_w(), img->data_h(), img->d(), img->ld(), img->array);
     }
   }
   Fl_Surface_Device::pop_current();
@@ -586,13 +658,13 @@ void Fl_GDI_Graphics_Driver::uncache(Fl_RGB_Image*, fl_uintptr_t &id_, fl_uintpt
   }
 
   if (mask_) {
-    fl_delete_bitmask((Fl_Bitmask)mask_);
+    delete_bitmask(mask_);
     mask_ = 0;
   }
 }
 
 // 'fl_create_bitmap()' - Create a 1-bit bitmap for drawing...
-static Fl_Bitmask fl_create_bitmap(int w, int h, const uchar *data) {
+static HBITMAP fl_create_bitmap(int w, int h, const uchar *data) {
   // we need to pad the lines out to words & swap the bits
   // in each byte.
   int w1 = (w + 7) / 8;
@@ -600,7 +672,7 @@ static Fl_Bitmask fl_create_bitmap(int w, int h, const uchar *data) {
   uchar* newarray = new uchar[w2*h];
   const uchar* src = data;
   uchar* dest = newarray;
-  Fl_Bitmask bm;
+  HBITMAP bm;
   static uchar reverse[16] =    /* Bit reversal lookup table */
   { 0x00, 0x88, 0x44, 0xcc, 0x22, 0xaa, 0x66, 0xee,
     0x11, 0x99, 0x55, 0xdd, 0x33, 0xbb, 0x77, 0xff };
@@ -731,8 +803,7 @@ void Fl_GDI_Graphics_Driver::cache(Fl_Pixmap *img) {
   fl_draw_pixmap(img->data(), 0, 0, FL_BLACK);
   uchar *bitmap = *pbitmap;
   if (bitmap) {
-    // call fl_create_bitmask here because "this" is not the current graphics driver
-    *Fl_Graphics_Driver::mask(img) = (fl_uintptr_t)fl_create_bitmask(img->data_w(), img->data_h(), bitmap);
+    *Fl_Graphics_Driver::mask(img) = (fl_uintptr_t)create_bitmask(img->data_w(), img->data_h(), bitmap);
     delete[] bitmap;
   }
   *pbitmap = 0;