issue #364, clip window support

cppsrc/U8g2lib.h

@@ -144,6 +144,12 @@ class U8G2 : public Print
 
     /* u8g2  */
 
+#ifdef U8G2_WITH_CLIP_WINDOW_SUPPORT
+    void setMaxClipWindow(void) { u8g2_SetMaxClipWindow(&u8g2); }
+    void setClipWindow(u8g2_uint_t clip_x0, u8g2_uint_t clip_y0, u8g2_uint_t clip_x1, u8g2_uint_t clip_y1) {
+      u8g2_SetClipWindow(&u8g2, clip_x0, clip_y0, clip_x1, clip_y1 ); }
+#endif /* U8G2_WITH_CLIP_WINDOW_SUPPORT */
+      
       
     u8g2_uint_t getDisplayHeight(void) { return u8g2_GetDisplayHeight(&u8g2); }
     u8g2_uint_t getDisplayWidth(void) { return u8g2_GetDisplayWidth(&u8g2); }

csrc/u8g2.h

@@ -82,6 +82,15 @@
 */
 #define U8G2_WITH_ONE_PIXEL_OPTIMIZATION
 
+/*
+  Enable clip window support:
+    void u8g2_SetMaxClipWindow(u8g2_t *u8g2)
+    void u8g2_SetClipWindow(u8g2_t *u8g2, u8g2_uint_t clip_x0, u8g2_uint_t clip_y0, u8g2_uint_t clip_x1, u8g2_uint_t clip_y1 )
+  Setting a clip window will restrict all drawing to this window.
+  Clip window support requires about 200 bytes flash memory on AVR systems
+*/
+//#define U8G2_WITH_CLIP_WINDOW_SUPPORT
+
 
 /*
   The following macro enables the HVLine speed optimization.
@@ -290,7 +299,7 @@ struct u8g2_struct
   u8g2_uint_t buf_y0;
   u8g2_uint_t buf_y1;
   
-  /* display dimensions in pixel for the user, calculated in u8g2_update_dimension_common(), used in u8g2_draw_hv_line_2dir() */
+  /* display dimensions in pixel for the user, calculated in u8g2_update_dimension_common()  */
   u8g2_uint_t width;
   u8g2_uint_t height;
   
@@ -302,6 +311,15 @@ struct u8g2_struct
   u8g2_uint_t user_y0;	/* upper edge of the buffer */
   u8g2_uint_t user_y1;	/* lower edge of the buffer (excluded) */
   
+#ifdef U8G2_WITH_CLIP_WINDOW_SUPPORT
+  /* clip window */
+  u8g2_uint_t clip_x0;	/* left corner of the clip window */
+  u8g2_uint_t clip_x1;	/* right corner of the clip window (excluded) */
+  u8g2_uint_t clip_y0;	/* upper edge of the clip window */
+  u8g2_uint_t clip_y1;	/* lower edge of the clip window (excluded) */
+#endif /* U8G2_WITH_CLIP_WINDOW_SUPPORT */
+  
+  
   /* information about the current font */
   const uint8_t *font;             /* current font for all text procedures */
   // removed: const u8g2_kerning_t *kerning;		/* can be NULL */
@@ -311,6 +329,11 @@ struct u8g2_struct
   u8g2_font_decode_t font_decode;		/* new font decode structure */
   u8g2_font_info_t font_info;			/* new font info structure */
 
+#ifdef U8G2_WITH_CLIP_WINDOW_SUPPORT
+  /* 1 of there is an intersection between user_?? and clip_?? box */
+  uint8_t is_page_clip_window_intersection;
+#endif /* U8G2_WITH_CLIP_WINDOW_SUPPORT */
+
   uint8_t font_height_mode;
   int8_t font_ref_ascent;
   int8_t font_ref_descent;
@@ -325,12 +348,6 @@ struct u8g2_struct
 	// the following variable should be renamed to is_buffer_auto_clear
   uint8_t is_auto_page_clear; 		/* set to 0 to disable automatic clear of the buffer in firstPage() and nextPage() */
   
-// removed, there is now the new index table
-//#ifdef __unix__
-//  uint16_t last_unicode;
-//  const uint8_t *last_font_data;
-//#endif
-
 };
 
 #define u8g2_GetU8x8(u8g2) ((u8x8_t *)(u8g2))
@@ -399,6 +416,9 @@ extern const u8g2_cb_t u8g2_cb_mirror;
       
 */
 
+void u8g2_SetMaxClipWindow(u8g2_t *u8g2);
+void u8g2_SetClipWindow(u8g2_t *u8g2, u8g2_uint_t clip_x0, u8g2_uint_t clip_y0, u8g2_uint_t clip_x1, u8g2_uint_t clip_y1 );
+
 void u8g2_SetupBuffer(u8g2_t *u8g2, uint8_t *buf, uint8_t tile_buf_height, u8g2_draw_ll_hvline_cb ll_hvline_cb, const u8g2_cb_t *u8g2_cb);
 void u8g2_SetDisplayRotation(u8g2_t *u8g2, const u8g2_cb_t *u8g2_cb);
 

csrc/u8g2_hvline.c

@@ -45,6 +45,8 @@
 #include "u8g2.h"
 #include <assert.h>
 
+/*==========================================================*/
+/* intersection procedure */
 
 /*
   Description:
@@ -114,6 +116,10 @@ static uint8_t u8g2_clip_intersection2(u8g2_uint_t *ap, u8g2_uint_t *len, u8g2_u
 }
 
 
+
+/*==========================================================*/
+/* draw procedures */
+
 /*
   x,y		Upper left position of the line within the pixel buffer 
   len		length of the line in pixel, len must not be 0
@@ -129,7 +135,7 @@ void u8g2_draw_hv_line_2dir(u8g2_t *u8g2, u8g2_uint_t x, u8g2_uint_t y, u8g2_uin
   /* clipping happens before the display rotation */
 
   /* transform to pixel buffer coordinates */
-  y -= u8g2->tile_curr_row*8;
+  y -= u8g2->pixel_curr_row;
   
   u8g2->ll_hvline(u8g2, x, y, len, dir);
 }
@@ -146,48 +152,52 @@ void u8g2_DrawHVLine(u8g2_t *u8g2, u8g2_uint_t x, u8g2_uint_t y, u8g2_uint_t len
   /* Make a call to the callback function (e.g. u8g2_draw_l90_r0). */
   /* The callback may rotate the hv line */
   /* after rotation this will call u8g2_draw_hv_line_4dir() */
-  if ( len != 0 )
-  {
   
-    /* convert to two directions */    
+#ifdef U8G2_WITH_CLIP_WINDOW_SUPPORT
-    if ( len > 1 )
+  if ( u8g2->is_page_clip_window_intersection != 0 )
+#endif /* U8G2_WITH_CLIP_WINDOW_SUPPORT */
+    if ( len != 0 )
     {
-      if ( dir == 2 )
+    
+      /* convert to two directions */    
+      if ( len > 1 )
       {
-	x -= len;
+	if ( dir == 2 )
-	x++;
+	{
+	  x -= len;
+	  x++;
+	}
+	else if ( dir == 3 )
+	{
+	  y -= len;
+	  y++;
+	}
       }
-      else if ( dir == 3 )
+      dir &= 1;  
+      
+      /* clip against the user window */
+      if ( dir == 0 )
       {
-	y -= len;
+	if ( y < u8g2->user_y0 )
-	y++;
+	  return;
+	if ( y >= u8g2->user_y1 )
+	  return;
+	if ( u8g2_clip_intersection2(&x, &len, u8g2->user_x0, u8g2->user_x1) == 0 )
+	  return;
       }
+      else
+      {
+	if ( x < u8g2->user_x0 )
+	  return;
+	if ( x >= u8g2->user_x1 )
+	  return;
+	if ( u8g2_clip_intersection2(&y, &len, u8g2->user_y0, u8g2->user_y1) == 0 )
+	  return;
+      }
+      
+      
+      u8g2->cb->draw_l90(u8g2, x, y, len, dir);
     }
-    dir &= 1;  
-    
-    /* clip against the user window */
-    if ( dir == 0 )
-    {
-      if ( y < u8g2->user_y0 )
-	return;
-      if ( y >= u8g2->user_y1 )
-	return;
-      if ( u8g2_clip_intersection2(&x, &len, u8g2->user_x0, u8g2->user_x1) == 0 )
-	return;
-    }
-    else
-    {
-      if ( x < u8g2->user_x0 )
-	return;
-      if ( x >= u8g2->user_x1 )
-	return;
-      if ( u8g2_clip_intersection2(&y, &len, u8g2->user_y0, u8g2->user_y1) == 0 )
-	return;
-    }
-    
-    
-    u8g2->cb->draw_l90(u8g2, x, y, len, dir);
-  }
 }
 
 void u8g2_DrawHLine(u8g2_t *u8g2, u8g2_uint_t x, u8g2_uint_t y, u8g2_uint_t len)

csrc/u8g2_setup.c

@@ -38,6 +38,30 @@
 #include <assert.h>
 
 
+/*============================================*/
+
+
+#ifdef U8G2_WITH_CLIP_WINDOW_SUPPORT
+void u8g2_SetMaxClipWindow(u8g2_t *u8g2)
+{
+  u8g2->clip_x0 = 0;
+  u8g2->clip_y0 = 0;
+  u8g2->clip_x1 = (u8g2_uint_t)~(u8g2_uint_t)0;
+  u8g2->clip_y1 = (u8g2_uint_t)~(u8g2_uint_t)0;
+}
+#endif
+
+#ifdef U8G2_WITH_CLIP_WINDOW_SUPPORT
+void u8g2_SetClipWindow(u8g2_t *u8g2, u8g2_uint_t clip_x0, u8g2_uint_t clip_y0, u8g2_uint_t clip_x1, u8g2_uint_t clip_y1 )
+{
+  u8g2->clip_x0 = clip_x0;
+  u8g2->clip_y0 = clip_y0;
+  u8g2->clip_x1 = clip_x1;
+  u8g2->clip_y1 = clip_y1;
+  u8g2->cb->update(u8g2);
+}
+#endif
+
 /*============================================*/
 /*
   This procedure is called after setting up the display (u8x8 structure).
@@ -64,6 +88,9 @@ void u8g2_SetupBuffer(u8g2_t *u8g2, uint8_t *buf, uint8_t tile_buf_height, u8g2_
   u8g2->is_auto_page_clear = 1;
   
   u8g2->cb = u8g2_cb;
+#ifdef U8G2_WITH_CLIP_WINDOW_SUPPORT
+  u8g2_SetMaxClipWindow(u8g2);		/* assign a clip window before the update() callback is called */
+#endif
   u8g2->cb->update(u8g2);
 
   u8g2_SetFontPosBaseline(u8g2);  /* issue 195 */
@@ -96,13 +123,14 @@ void u8g2_SetDisplayRotation(u8g2_t *u8g2, const u8g2_cb_t *u8g2_cb)
 
 static void u8g2_update_dimension_common(u8g2_t *u8g2)
 {
+  const u8x8_display_info_t *display_info = u8g2_GetU8x8(u8g2)->display_info;
   u8g2_uint_t t;
   
   t = u8g2->tile_buf_height;
   t *= 8;
   u8g2->pixel_buf_height = t;
   
-  t = u8g2_GetU8x8(u8g2)->display_info->tile_width;
+  t = display_info->tile_width;
 #ifndef U8G2_16BIT
   if ( t >= 32 )
     t = 31;
@@ -116,8 +144,8 @@ static void u8g2_update_dimension_common(u8g2_t *u8g2)
   
   t = u8g2->tile_buf_height;
   /* handle the case, where the buffer is larger than the (remaining) part of the display */
-  if ( t + u8g2->tile_curr_row > u8g2_GetU8x8(u8g2)->display_info->tile_height )
+  if ( t + u8g2->tile_curr_row > display_info->tile_height )
-    t = u8g2_GetU8x8(u8g2)->display_info->tile_height - u8g2->tile_curr_row;
+    t = display_info->tile_height - u8g2->tile_curr_row;
   t *= 8;
   
   u8g2->buf_y0 = u8g2->pixel_curr_row;   
@@ -126,17 +154,47 @@ static void u8g2_update_dimension_common(u8g2_t *u8g2)
 
   
 #ifdef U8G2_16BIT
-  u8g2->width = u8g2_GetU8x8(u8g2)->display_info->pixel_width;
+  u8g2->width = display_info->pixel_width;
-  u8g2->height = u8g2_GetU8x8(u8g2)->display_info->pixel_height;
+  u8g2->height = display_info->pixel_height;
 #else
   u8g2->width = 240;
-  if ( u8g2_GetU8x8(u8g2)->display_info->pixel_width <= 240 )
+  if ( display_info->pixel_width <= 240 )
-    u8g2->width = u8g2_GetU8x8(u8g2)->display_info->pixel_width;
+    u8g2->width = display_info->pixel_width;
-  u8g2->height = u8g2_GetU8x8(u8g2)->display_info->pixel_height;
+  u8g2->height = display_info->pixel_height;
 #endif
 
 }
 
+/*==========================================================*/
+/* apply clip window */
+
+#ifdef U8G2_WITH_CLIP_WINDOW_SUPPORT
+static void u8g2_apply_clip_window(u8g2_t *u8g2)
+{
+  /* check aganst the current user_??? window */
+  if ( u8g2_IsIntersection(u8g2, u8g2->clip_x0, u8g2->clip_y0, u8g2->clip_x1, u8g2->clip_y1) == 0 ) 
+  {
+    u8g2->is_page_clip_window_intersection = 0;
+  }
+  else
+  {
+    u8g2->is_page_clip_window_intersection = 1;
+
+    if ( u8g2->user_x0 < u8g2->clip_x0 )
+      u8g2->user_x0 = u8g2->clip_x0;
+    if ( u8g2->user_x1 > u8g2->clip_x1 )
+      u8g2->user_x1 = u8g2->clip_x1;
+    if ( u8g2->user_y0 < u8g2->clip_y0 )
+      u8g2->user_y0 = u8g2->clip_y0;
+    if ( u8g2->user_y1 > u8g2->clip_y1 )
+      u8g2->user_y1 = u8g2->clip_y1;
+  }
+}
+#endif /* U8G2_WITH_CLIP_WINDOW_SUPPORT */
+
+/*==========================================================*/
+
+
 void u8g2_update_dimension_r0(u8g2_t *u8g2)
 {
   u8g2_update_dimension_common(u8g2);
@@ -147,6 +205,10 @@ void u8g2_update_dimension_r0(u8g2_t *u8g2)
   u8g2->user_y0 = u8g2->buf_y0;
   u8g2->user_y1 = u8g2->buf_y1;
   
+#ifdef U8G2_WITH_CLIP_WINDOW_SUPPORT
+  u8g2_apply_clip_window(u8g2);
+#endif /* U8G2_WITH_CLIP_WINDOW_SUPPORT */
+  
 //  printf("x0=%d x1=%d y0=%d y1=%d\n", 
 //      u8g2->user_x0, u8g2->user_x1, u8g2->user_y0, u8g2->user_y1);
 }
@@ -164,6 +226,9 @@ void u8g2_update_dimension_r1(u8g2_t *u8g2)
   u8g2->user_y0 = 0;
   u8g2->user_y1 = u8g2->height;	/* pixel_buf_width replaced with height (which is the real pixel width) */
   
+#ifdef U8G2_WITH_CLIP_WINDOW_SUPPORT
+  u8g2_apply_clip_window(u8g2);
+#endif /* U8G2_WITH_CLIP_WINDOW_SUPPORT */
   //printf("x0=%d x1=%d y0=%d y1=%d\n", 
    //   u8g2->user_x0, u8g2->user_x1, u8g2->user_y0, u8g2->user_y1);
 }
@@ -182,6 +247,9 @@ void u8g2_update_dimension_r2(u8g2_t *u8g2)
     u8g2->user_y0 = u8g2->height - u8g2->buf_y1;
   u8g2->user_y1 = u8g2->height - u8g2->buf_y0;
 
+#ifdef U8G2_WITH_CLIP_WINDOW_SUPPORT
+  u8g2_apply_clip_window(u8g2);
+#endif /* U8G2_WITH_CLIP_WINDOW_SUPPORT */
 //  printf("x0=%d x1=%d y0=%d y1=%d\n", 
 //      u8g2->user_x0, u8g2->user_x1, u8g2->user_y0, u8g2->user_y1);
 }
@@ -203,6 +271,9 @@ void u8g2_update_dimension_r3(u8g2_t *u8g2)
   u8g2->user_y0 = 0;
   u8g2->user_y1 = u8g2->height;	/* pixel_buf_width replaced with height (pixel_width) */
 
+#ifdef U8G2_WITH_CLIP_WINDOW_SUPPORT
+  u8g2_apply_clip_window(u8g2);
+#endif /* U8G2_WITH_CLIP_WINDOW_SUPPORT */
 //  printf("x0=%d x1=%d y0=%d y1=%d\n", 
 //      u8g2->user_x0, u8g2->user_x1, u8g2->user_y0, u8g2->user_y1);
 }

sys/arduino/u8g2_page_buffer/HelloWorld/HelloWorld.ino

@@ -38,6 +38,8 @@
    8440	    152	    420	   9012	   2334	HelloWorld.elf
    
   8422
+  8470
+  8676
 
 */