[freetype2-demos] master e5cf9c9 2/2: src/ftgamma.c: Center and clip the bitmap to fix resizing.

[Alexei Podtelezhnikov]

branch: master
commit e5cf9c9f8997418e834a52f67e24a4c0b926e502
Author: Alexei Podtelezhnikov <apodtele@gmail.com>
Commit: Alexei Podtelezhnikov <apodtele@gmail.com>

    src/ftgamma.c: Center and clip the bitmap to fix resizing.
---
 ChangeLog     |  4 ++++
 src/ftgamma.c | 71 +++++++++++++++++++++++++++++++++++++++--------------------
 2 files changed, 51 insertions(+), 24 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index ed5675f..18574c7 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
 2020-05-28  Alexei Podtelezhnikov  <apodtele@gmail.com>
 
+       src/ftgamma.c: Center and clip the bitmap to fix resizing.
+
+2020-05-28  Alexei Podtelezhnikov  <apodtele@gmail.com>
+
        [graph/x11] Stop double-dealing BackSpace, Tab, Return, and Esc.
 
        * graph/x11/grx11.c (gr_x11_surface_listen_event): Do not reset the
diff --git a/src/ftgamma.c b/src/ftgamma.c
index 0cd398e..088a0fe 100644
--- a/src/ftgamma.c
+++ b/src/ftgamma.c
@@ -285,36 +285,50 @@
                  int        lcd )
   {
     int  pitch = abs( out->pitch );
+    int  l = 0, r = in->width, t = 0, b = in->rows;
     int  i, ii, j;
 
     unsigned char*  src;
     unsigned char*  dst;
 
 
+    /* clip if necessary */
+    if ( x < 0 )
+      l = -x;
+    if ( y < 0 )
+      t = -y;
+    if ( x + r > out->width )
+      r = out->width - x;
+    if ( y + b > out->rows )
+      b = out->rows - y;
+
     if ( color.chroma[0] == 255 )
-      for ( src = in->buffer, i = 0; i < in->rows; i++ )
+      for ( i = t; i < b; i++ )
       {
-        ii = ( i + 24 * lcd ) % in->rows;
-        dst = out->buffer + ( y + ii ) * pitch + 3 * x;
-        for ( j = 0; j < in->width; j++, src++, dst += 3 )
+        ii = ( i +  0 * lcd ) % in->rows;
+        src = in->buffer + ii * in->pitch + l;
+        dst = out->buffer + ( y + i ) * pitch + 3 * ( x + l );
+        for ( j = l; j < r; j++, src++, dst += 3 )
           *dst = *src;
       }
 
     if ( color.chroma[1] == 255 )
-      for ( src = in->buffer, i = 0; i < in->rows; i++ )
+      for ( i = t; i < b; i++ )
       {
         ii = ( i + 12 * lcd ) % in->rows;
-        dst = out->buffer + ( y + ii ) * pitch + 3 * x + 1;
-        for ( j = 0; j < in->width; j++, src++, dst += 3 )
+        src = in->buffer + ii * in->pitch + l;
+        dst = out->buffer + ( y + i ) * pitch + 3 * ( x + l ) + 1;
+        for ( j = l; j < r; j++, src++, dst += 3 )
           *dst = *src;
       }
 
     if ( color.chroma[2] == 255 )
-      for ( src = in->buffer, i = 0; i < in->rows; i++ )
+      for ( i = t; i < b; i++ )
       {
-        ii = ( i +  0 * lcd ) % in->rows;
-        dst = out->buffer + ( y + ii ) * pitch + 3 * x + 2;
-        for ( j = 0; j < in->width; j++, src++, dst += 3 )
+        ii = ( i + 24 * lcd ) % in->rows;
+        src = in->buffer + ii * in->pitch + l;
+        dst = out->buffer + ( y + i ) * pitch + 3 * ( x + l ) + 2;
+        for ( j = l; j < r; j++, src++, dst += 3 )
           *dst = *src;
       }
   }
@@ -329,6 +343,9 @@
 
     grListenSurface( display->surface, 0, &event );
 
+    if ( event.type == gr_event_resize )
+      return ret;
+
     switch ( event.key )
     {
     case grKeyEsc:
@@ -387,36 +404,42 @@
 
     do
     {
+      int  x = display->bitmap->width / 2;
+      int  y = display->bitmap->rows / 2;
+
+
       FTDemo_Display_Clear( display );
 
       switch ( status )
       {
       case 0:
-        grWriteCellString( display->bitmap, 236, 75, "Solid-Checkered Pattern",
-                           display->fore_color );
-        Render_Bitmap( display->bitmap, &bit1, 20, 90, display->fore_color, 0 
);
+        grWriteCellString( display->bitmap, x - 84, y - 165,
+                           "Solid-Checkered Pattern", display->fore_color );
+        Render_Bitmap( display->bitmap, &bit1, x - 300, y - 150,
+                       display->fore_color, 0 );
         break;
       case 1:
-        grWriteCellString( display->bitmap, 236, 75, "Grayscale Anti-Aliasing",
-                           display->fore_color );
-        Render_Bitmap( display->bitmap, &bit2, 20, 96, display->fore_color, 0 
);
+        grWriteCellString( display->bitmap, x - 84, y - 165,
+                           "Grayscale Anti-Aliasing", display->fore_color );
+        Render_Bitmap( display->bitmap, &bit2, x - 300, y - 144,
+                       display->fore_color, 0 );
         break;
       case 2:
-        grWriteCellString( display->bitmap, 236, 75, "Subpixel  Anti-Aliasing",
-                           display->fore_color );
-        Render_Bitmap( display->bitmap, &bit2, 20, 96, display->fore_color, 1 
);
+        grWriteCellString( display->bitmap, x - 84, y - 165,
+                           "Subpixel  Anti-Aliasing", display->fore_color );
+        Render_Bitmap( display->bitmap, &bit2, x - 300, y - 144,
+                       display->fore_color, 1 );
         break;
       }
 
       for ( i = 0; i <= 10; i++ )
       {
         sprintf( buf, "%.1f", 1. + .2 * i );
-        grWriteCellString( display->bitmap, 9 + i * 60, 395, buf,
-                           display->fore_color );
+        grWriteCellString( display->bitmap, x - 311 + i * 60, y + 155,
+                           buf, display->fore_color );
       }
 
-      grWriteCellString( display->bitmap,
-                         display->bitmap->width / 2 - 20, 410,
+      grWriteCellString( display->bitmap, x - 20, y + 170,
                          "Gamma", display->fore_color );
 
       grRefreshSurface( display->surface );