sdl_runrowstretchcode(3) [debian man page]

SDL_SETROWSTRETCHCOD(3) 					   Manual Pages 					   SDL_SETROWSTRETCHCOD(3)

NAME

       SDL_SetRowStretchCode, SDL_PutRowStretchCode, SDL_RunRowStretchCode, SDL_StretchRow1, SDL_StretchRow2, SDL_StretchRow3, SDL_StretchRow4 -
       (src/SDL_stretchcode.h)

SYNOPSIS

	#include <SDL_stretch.h>

       unsigned char* SDL_SetRowStretchCode(int src_w, int dst_w, int bpp);

       unsigned char* SDL_PutRowStretchCode(unsigned char* buffer, int buflen, int src_w, int dst_w, int bpp);

       void SDL_RunRowStretchCode(unsigned char* buffer, unsigned char* src, unsigned char* dst);

       void SDL_StretchRow1(Uint8 *src, int src_w, Uint8 *dst, int dst_w);

       void SDL_StretchRow2(Uint16 *src, int src_w, Uint16 *dst, int dst_w);

       void SDL_StretchRow3(Uint8 *src, int src_w, Uint8 *dst, int dst_w);

       void SDL_StretchRow4(Uint32 *src, int src_w, Uint32 *dst, int dst_w);

DESCRIPTION

       The SetRowStretchCode is a wrapper around PutRowStretchCode that uses the Adress and Size of the shared SDL_TheRowStretchCode buffer. The
       PutRowStretchCode will fill the given buffer with an assembler stream that should be called with SDL_RunRowStretchCode. The assembler
       stream is usually faster as all the scale decisions are done in advance of the execution. This helps when a RunCode is done multiple times
       with the same src_w/dst_w/bpp pair. All the pixel-get and pixel-set calls are unrolled in that buffer. Therefore, the buffer should be big
       enough - as a rule of thumb use a buffer of size (src_w+dst_w)*5

       If PutCode or SetCode fails, a NULL is returned and SDL_SetError. Otherwise, the start adress of the machine code buffer is returned, which
       is also the input argument of PutCode and RunCode.

       If SDL_SetRowStretchCode fails, the SDL_StretchRow1 function must be used instead.  The SDL_StretchRow1 function and its cousins are
       singular routines that work in a tight loop to scale a single row. The number specifies the byte-width of each pixel (it is not a
       bit-width!).

SDL_stretch							       0.3.1						   SDL_SETROWSTRETCHCOD(3)

IMAGECOPYRESIZED(3)							 1						       IMAGECOPYRESIZED(3)

imagecopyresized - Copy and resize part of an image

SYNOPSIS

       bool  imagecopyresized  (resource   $dst_image,	resource  $src_image, int  $dst_x, int	$dst_y, int  $src_x, int  $src_y, int  $dst_w, int
       $dst_h, int  $src_w, int  $src_h)

DESCRIPTION

       imagecopyresized(3) copies a rectangular portion of one image to another image. $dst_image is the  destination  image,  $src_image  is  the
       source image identifier.

	In  other  words,  imagecopyresized(3)	will  take  a  rectangular  area  from	$src_image  of	width $src_w and height $src_h at position
       ($src_x,$src_y) and place it in a rectangular area of $dst_image of width $dst_w and height $dst_h at position ($dst_x,$dst_y).

	If the source and destination coordinates and width and heights differ, appropriate stretching or shrinking of the image fragment will	be
       performed.  The	coordinates refer to the upper left corner. This function can be used to copy regions within the same image (if $dst_image
       is the same as $src_image) but if the regions overlap the results will be unpredictable.

PARAMETERS

	      o $dst_image
		-Destination image link resource.

	      o $src_image
		-Source image link resource.

	      o $dst_x
		- x-coordinate of destination point.

	      o $dst_y
		- y-coordinate of destination point.

	      o $src_x
		- x-coordinate of source point.

	      o $src_y
		- y-coordinate of source point.

	      o $dst_w
		- Destination width.

	      o $dst_h
		- Destination height.

	      o $src_w
		-Source width.

	      o $src_h
		-Source height.

RETURN VALUES

	Returns TRUE on success or FALSE on failure.

EXAMPLES

       Example #1

	      Resizing an image

	       This example will display the image at half size.

	      <?php
	      // File and new size
	      $filename = 'test.jpg';
	      $percent = 0.5;

	      // Content type
	      header('Content-Type: image/jpeg');

	      // Get new sizes
	      list($width, $height) = getimagesize($filename);
	      $newwidth = $width * $percent;
	      $newheight = $height * $percent;

	      // Load
	      $thumb = imagecreatetruecolor($newwidth, $newheight);
	      $source = imagecreatefromjpeg($filename);

	      // Resize
	      imagecopyresized($thumb, $source, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);

	      // Output
	      imagejpeg($thumb);
	      ?>

	      The above example will output something similar to:[NOT DISPLAYABLE MEDIA]Output of example : Resizing an image

	       The image will be output at half size, though better quality could be obtained using imagecopyresampled(3).

NOTES

       Note

	       There is a problem due to palette image limitations (255+1 colors). Resampling or filtering an image  commonly  needs  more  colors
	      than  255,  a kind of approximation is used to calculate the new resampled pixel and its color. With a palette image we try to allo-
	      cate a new color, if that failed, we choose the closest (in theory) computed color. This is not always  the  closest  visual  color.
	      That may produce a weird result, like blank (or visually blank) images. To skip this problem, please use a truecolor image as a des-
	      tination image, such as one created by imagecreatetruecolor(3).

SEE ALSO

       imagecopyresampled(3)

PHP Documentation Group 												       IMAGECOPYRESIZED(3)