draw.c

sharp的arm920t 7A400的评估板附带光盘Sharp KEVLH7A400 v0.3b Welcome to the SHARP KEV7A400 Evaluation board

/**********************************************************************
 *	$Workfile:   draw.c  $
 *	$Revision:   1.0  $
 *	$Author:   WellsK  $
 *	$Date:   Sep 23 2002 13:54:18  $
 *
 *	Project: LH7A400
 *
 *	Description:
 *     Basic draw functions (line, box, circle). All pixel coordinates
 *     are positive. (X=0, Y=0 is the upper left hand corner of the
 *     display).
 *
 *  Note
 *     Pen width is current not implemented.
 *
 *	References:
 *      None
 *
 *	Revision History:
 *	$Log:   //smaicnt2/pvcs/VM/CDROM/archives/KEV7A400/Software/Board applications/Simple startup demo/draw.c-arc  $
 * 
 *    Rev 1.0   Sep 23 2002 13:54:18   WellsK
 * Initial revision.
 * 
 *
 *	COPYRIGHT (C) 2001 SHARP MICROELECTRONICS OF THE AMERICAS, INC.
 *		CAMAS, WA
 *********************************************************************/
#include "draw.h"

// Maximum X and Y display coordinates
int xlim, ylim;

// Saved address of frame buffer (must be physical address)
UNS_16 *frame_addr;

// Pen widths and colors
UNS_16 draw_pen_width;
UNS_16 draw_pen_color;
UNS_16 draw_fill_color;

/**********************************************************************
*
* Function: draw_init
*
* Purpose:
*   Initialize the draw package, set the frame buffer base address
*
* Processing:
*  TBD
*
* Parameters: 
*  fb_addr: Physical address of the frame buffer 
*  xmax   : Maximum X value of the display
*  ymax   : Maximum Y value of the display
*
* Outputs: None
*
* Returns: Nothing
*
* Notes:
*
**********************************************************************/
void draw_init (UNS_16 *fb_addr, int xmax, int ymax)
{
   // Save display and frame buffer settings
   frame_addr = fb_addr;
   xlim = xmax;
   ylim = ymax;

   // Set default colors and widths
   draw_pen_width = 1;
   draw_pen_color = 0x0;
   draw_fill_color = 0x0;
}

/**********************************************************************
*
* Function: draw_set_pen_width
*
* Purpose:
*   Set the pen width (in pixels)
*
* Processing:
*  TBD
*
* Parameters: 
*  pen_width: Pen width in pixels 
*
* Outputs: None
*
* Returns: Nothing
*
* Notes:
*
**********************************************************************/
void draw_set_pen_width (int pen_width)
{
   draw_pen_width = pen_width;
}

/**********************************************************************
*
* Function: draw_set_pen_width
*
* Purpose:
*   Set the pen color
*
* Processing:
*  TBD
*
* Parameters: 
*  pen_width: Pen width in pixels 
*
* Outputs: None
*
* Returns: Nothing
*
* Notes:
*
**********************************************************************/
void draw_set_pen_color (UNS_16 pen_color)
{
   draw_pen_color = pen_color;
}

/**********************************************************************
*
* Function: draw_set_pen_width
*
* Purpose:
*   Set fill color (used for boxes and circles)
*
* Processing:
*  TBD
*
* Parameters: 
*  pen_width: Pen width in pixels 
*
* Outputs: None
*
* Returns: Nothing
*
* Notes:
*
**********************************************************************/
void draw_set_fill_color (UNS_16 fill_color)
{
   draw_fill_color = fill_color;
}

/**********************************************************************
*
* Function: draw_line
*
* Purpose:
*   Draw a line from (X1, Y1) to (X2, Y2)
*
* Processing:
*  TBD
*
* Parameters: 
*  x1: Upper left X coordinate
*  y1: Upper left Y coordinate
*  x2: Lower left X coordinate
*  y2: Lower left Y coordinate
*
* Outputs: None
*
* Returns: Nothing
*
* Notes:
*
**********************************************************************/
void draw_line (int x1, int y1, int x2, int y2)
{
   int xinc, yinc;
   int pixel_start, pixel_end;
   int line;
   int xv, yv;
   int offs;

   // Drawing is performed at a much 'higher' resolution that the
   // actual display. Before writing to the frame buffer, the 'lower'
   // resolution is restored. xscale and yscale are virtual limits
   // for the display size

   // Swap x1 and x2 if x1 is larger than x2
   if (x1 > x2)
   {
      xinc = x1;
      x1 = x2;
      x2 = xinc;
   }

   // Swap y1 and y2 if y1 is larger than y2
   if (y1 > y2)
   {
      yinc = y1;
      y1 = y2;
      y2 = yinc;
   }

   // Clip edges of display
   if (x1 < 0) x1 = 0;
   if (y1 < 0) y1 = 0;
   if (x2 >= xlim) x2 = xlim - 1;
   if (y2 >= ylim) y2 = ylim - 1;

   // Determine difference X and Y values
   xinc = x2 - x1;
   yinc = y2 - y1;

   // Use the X or Y axis for drawing (whichever is longer)
   if ((xinc == 0) && (yinc == 0))
   {
      pixel_start = x1;   // Starting virtual pixel
      pixel_end = x2;     // Ending virtual pixel

      xinc = xlim;
      yinc = ylim;
   }
   if (xinc > yinc)
   {
      // Use X axis for drawing
      pixel_start = x1;   // Starting virtual pixel
      pixel_end = x2;     // Ending virtual pixel

      // Determine incremental values for X and Y
      yinc = ylim * yinc / xinc;
      xinc = xlim;
   }
   else
   {
      // Use Y axis for drawing
      pixel_start = y1;   // Starting virtual pixel
      pixel_end = y2;     // Ending virtual pixel

      // Determine scaling factors
      xinc = xlim * xinc / yinc;
      yinc = ylim;
   }

   // Starting virtual X and Y values
   xv = x1 * xlim;
   yv = y1 * ylim;

   // Draw line
   for (line = pixel_start; line <= pixel_end;)
   {
      // Convert virtual pixel address into real offset
      offs = (xv / xlim) + (yv / ylim) * xlim;

      * (frame_addr + offs) = draw_pen_color;

      // Increment X and Y virtual pixel locations
      xv = xv + xinc;
      yv = yv + yinc;

      // Increment to next virtual pixel
      line++;
   }
}

/**********************************************************************
*
* Function: draw_box
*
* Purpose:
*   Place a box with corners (X1, Y1) and (X2, Y2)
*
* Processing:
*  TBD
*
* Parameters: 
*  x1: Upper left X coordinate
*  y1: Upper left Y coordinate
*  x2: Lower left X coordinate
*  y2: Lower left Y coordinate
*
* Outputs: None
*
* Returns: Nothing
*
* Notes:
*
**********************************************************************/
void draw_box (int x1, int y1, int x2, int y2)
{
   int xinc, yinc;
   int xlines, ylines;
   int x, y;

   if (x1 > x2)
   {
      xinc = x1;
      x1 = x2;
      x2 = xinc;
   }

   // Swap y1 and y2 if y1 is larger than y2
   if (y1 > y2)
   {
      yinc = y1;
      y1 = y2;
      y2 = yinc;
   }

   // Clip edges of display
   if (x1 < 0) x1 = 0;
   if (y1 < 0) y1 = 0;
   if (x2 >= xlim) x2 = xlim - 1;
   if (y2 >= ylim) y2 = ylim - 1;

   // Get X and Y differences
   xinc = x2 - x1;
   yinc = y2 - y1;

   // Number of X and Y lines to put with fill color
   xlines = xinc - 2;
   ylines = yinc - 2;

   // First, draw the 'guts' with the fill color
   if ((xlines > 0) && (ylines > 0))
   {
      for (x = (x1 + 1); x < x2; x++)
      {
         for (y = (y1 + 1); y < y2; y++)
         {
            * (frame_addr + x + (y * xlim)) = draw_fill_color;
         }
      }
   }

   // Make outer edge of box in pen color
   draw_line (x1, y1, x2, y1);
   draw_line (x2, y1, x2, y2);
   draw_line (x2, y2, x1, y2);
   draw_line (x1, y2, x1, y1);
}

/**********************************************************************
*
* Function: draw_circle
*
* Purpose:
*   Place a circle with center (X1, Y1) and radius RAD (in pixels)
*
* Processing:
*  TBD
*
* Parameters: 
*  None
*
* Outputs: None
*
* Returns: Nothing
*
* Notes:
*
**********************************************************************/
void draw_circle (int x1, int y1, int RAD)
{
   ;
}

/**********************************************************************
*
* Function: draw_clear_screen
*
* Purpose:
*   Fills the display with the active fill color
*
* Processing:
*  TBD
*
* Parameters: 
*  None
*
* Outputs: None
*
* Returns: Nothing
*
* Notes:
*
**********************************************************************/
void draw_clear_screen (void)
{
   int J;

   for (J = 0; J < (xlim * ylim); J++)
   {
      * (frame_addr + J) = draw_fill_color;
   }
}

/**********************************************************************
*
* Function: draw_pixel
*
* Purpose:
*   Puts a pixel at (X, Y) in the pen color
*
* Processing:
*  TBD
*
* Parameters: 
*  x1: X coordinate
*  y1: Y coordinate
*
* Outputs: None
*
* Returns: Nothing
*
* Notes:
*
**********************************************************************/
void draw_pixel (int x1, int y1)
{
   * (frame_addr + x1 + (y1 * xlim)) = draw_pen_color;
}