PLplot  5.10.0
mem.c
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00001 // PLplot MEM (in user-supplied memory) device driver.
00002 // The idea here is that the user will specify the Y by X by RGB
00003 // area in which to plot using the plsmem function (added by me).
00004 //
00005 // This is a bare-bones driver which allows one to plot on an existing
00006 // image in memory.  This is useful if the user has an image in memory
00007 // that he wants to decorate with PLPLOT.
00008 //
00009 // Contributed by Doug Hunt
00010 // Included in PLplot by Rafael Laboissiere on Sat Feb 22 18:34:06 CET 2003
00011 //
00012 
00013 #include "plDevs.h"
00014 
00015 #ifdef PLD_mem
00016 
00017 #include "plplotP.h"
00018 #include "drivers.h"
00019 
00020 // Device info
00021 PLDLLIMPEXP_DRIVER const char* plD_DEVICE_INFO_mem = "mem:User-supplied memory device:-1:mem:46:mem\n";
00022 
00023 void plD_dispatch_init_mem( PLDispatchTable *pdt );
00024 
00025 void plD_init_mem( PLStream * );
00026 void plD_line_mem( PLStream *, short, short, short, short );
00027 void plD_polyline_mem( PLStream *, short *, short *, PLINT );
00028 void plD_eop_mem( PLStream * );
00029 void plD_bop_mem( PLStream * );
00030 void plD_tidy_mem( PLStream * );
00031 void plD_state_mem( PLStream *, PLINT );
00032 void plD_esc_mem( PLStream *, PLINT, void * );
00033 
00034 #undef MAX
00035 #undef ABS
00036 #define MAX( a, b )    ( ( a > b ) ? a : b )
00037 #define ABS( a )       ( ( a < 0 ) ? -a : a )
00038 
00039 #define MAX_INTENSITY    255
00040 
00041 void plD_dispatch_init_mem( PLDispatchTable *pdt )
00042 {
00043 #ifndef ENABLE_DYNDRIVERS
00044     pdt->pl_MenuStr = "User-supplied memory device";
00045     pdt->pl_DevName = "mem";
00046 #endif
00047     pdt->pl_type     = plDevType_Null;
00048     pdt->pl_seq      = 45;
00049     pdt->pl_init     = (plD_init_fp) plD_init_mem;
00050     pdt->pl_line     = (plD_line_fp) plD_line_mem;
00051     pdt->pl_polyline = (plD_polyline_fp) plD_polyline_mem;
00052     pdt->pl_eop      = (plD_eop_fp) plD_eop_mem;
00053     pdt->pl_bop      = (plD_bop_fp) plD_bop_mem;
00054     pdt->pl_tidy     = (plD_tidy_fp) plD_tidy_mem;
00055     pdt->pl_state    = (plD_state_fp) plD_state_mem;
00056     pdt->pl_esc      = (plD_esc_fp) plD_esc_mem;
00057 }
00058 
00059 //--------------------------------------------------------------------------
00060 // plD_init_mem()
00061 //
00062 // Initialize device (terminal).
00063 //--------------------------------------------------------------------------
00064 
00065 void
00066 plD_init_mem( PLStream *pls )
00067 {
00068     // plsmem must have already been called to set pls->dev to the
00069     // user supplied plotting area.  The dimensions of the plot area
00070     // have also been set by plsmem.  Verify this.
00071     //
00072 
00073     if ( ( pls->phyxma == 0 ) || ( pls->dev == NULL ) )
00074     {
00075         plexit( "Must call plsmem first to set user plotting area!" );
00076     }
00077 
00078     if ( pls->dev_mem_alpha == 1 )
00079     {
00080         plexit( "The mem driver does not support alpha values! Use plsmem!" );
00081     }
00082 
00083     plP_setpxl( (PLFLT) 4, (PLFLT) 4 ); // rough pixels/mm on *my* screen
00084 
00085 
00086     pls->color     = 1;         // Is a color device
00087     pls->dev_fill0 = 0;         // Handle solid fills
00088     pls->dev_fill1 = 0;         // Use PLplot core fallback for pattern fills
00089     pls->nopause   = 1;         // Don't pause between frames
00090 }
00091 
00092 #define sign( a )    ( ( a < 0 ) ? -1 : ( ( a == 0 ) ? 0 : 1 ) )
00093 
00094 // Modified version of the ljii routine (see ljii.c)
00095 void
00096 plD_line_mem( PLStream *pls, short x1a, short y1a, short x2a, short y2a )
00097 {
00098     int           i;
00099     PLINT         idx;
00100     int           x1 = x1a, y1 = y1a, x2 = x2a, y2 = y2a;
00101     PLINT         x1b, y1b, x2b, y2b;
00102     PLFLT         length, fx, fy, dx, dy;
00103     unsigned char *mem = (unsigned char *) pls->dev;
00104     PLINT         xm   = pls->phyxma;
00105     PLINT         ym   = pls->phyyma;
00106 
00107     // Take mirror image, since (0,0) must be at top left
00108 
00109     y1 = ym - ( y1 - 0 );
00110     y2 = ym - ( y2 - 0 );
00111 
00112     x1b    = x1, x2b = x2, y1b = y1, y2b = y2;
00113     length = (PLFLT) sqrt( (double)
00114         ( ( x2b - x1b ) * ( x2b - x1b ) + ( y2b - y1b ) * ( y2b - y1b ) ) );
00115 
00116     if ( length == 0. )
00117         length = 1.;
00118     dx = ( x2 - x1 ) / length;
00119     dy = ( y2 - y1 ) / length;
00120 
00121     fx = x1;
00122     fy = y1;
00123     mem[3 * xm * y1 + 3 * x1 + 0] = pls->curcolor.r;
00124     mem[3 * xm * y1 + 3 * x1 + 1] = pls->curcolor.g;
00125     mem[3 * xm * y1 + 3 * x1 + 2] = pls->curcolor.b;
00126 
00127     mem[3 * xm * y2 + 3 * x2 + 0] = pls->curcolor.r;
00128     mem[3 * xm * y2 + 3 * x2 + 1] = pls->curcolor.g;
00129     mem[3 * xm * y2 + 3 * x2 + 2] = pls->curcolor.b;
00130 
00131     for ( i = 1; i <= (int) length; i++ )
00132     {
00133         fx          += dx;
00134         fy          += dy;
00135         idx          = 3 * xm * (PLINT) fy + 3 * (PLINT) fx;
00136         mem[idx + 0] = pls->curcolor.r;
00137         mem[idx + 1] = pls->curcolor.g;
00138         mem[idx + 2] = pls->curcolor.b;
00139     }
00140 }
00141 
00142 void
00143 plD_polyline_mem( PLStream *pls, short *xa, short *ya, PLINT npts )
00144 {
00145     int i;
00146     for ( i = 0; i < npts - 1; i++ )
00147         plD_line_mem( pls, xa[i], ya[i], xa[i + 1], ya[i + 1] );
00148 }
00149 
00150 void
00151 plD_eop_mem( PLStream *pls )
00152 {
00153     // Set the 'dev' member (which holds the user supplied memory image)
00154     // to NULL here so it won't be freed when PLplot is closed.
00155     // (the user is responsible for freeing it when ready).
00156     //
00157     pls->dev = NULL;
00158 }
00159 
00160 void
00161 plD_bop_mem( PLStream * PL_UNUSED( pls ) )
00162 {
00163 // Nothing to do here
00164 }
00165 
00166 void
00167 plD_tidy_mem( PLStream * PL_UNUSED( pls ) )
00168 {
00169 // Nothing to do here
00170 }
00171 
00172 void
00173 plD_state_mem( PLStream * PL_UNUSED( pls ), PLINT PL_UNUSED( op ) )
00174 {
00175 // Nothing to do here
00176 }
00177 
00178 void
00179 plD_esc_mem( PLStream *PL_UNUSED( pls ), PLINT PL_UNUSED( op ), void * PL_UNUSED( ptr ) )
00180 {
00181 // Nothing to do here
00182 }
00183 
00184 #endif                          // PLD_mem
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