source/pixelstore.cpp

   1 #include <algorithm>
   2 #include "gl.h"
   3 #include "pixelformat.h"
   4 #include "pixelstore.h"
   5
   6 using namespace std;
   7
   8 namespace Msp {
   9 namespace GL {
  10
  11 PixelStore::PixelStore():
  12         row_length(0),
  13         image_height(0),
  14         skip_pixels(0),
  15         skip_rows(0),
  16         skip_images(0),
  17         alignment(4)
  18 { }
  19
  20 PixelStore PixelStore::from_image(const Graphics::Image &img)
  21 {
  22         PixelStore pstore;
  23         unsigned stride = img.get_stride();
  24         unsigned ncomp = get_component_count(pixelformat_from_graphics(img.get_format()));
  25         pstore.set_canvas_size(img.get_stride()/ncomp, 0);
  26         pstore.set_alignment(min(stride&~(stride-1), 8U));
  27         return pstore;
  28 }
  29
  30 void PixelStore::set_canvas_size(unsigned w, unsigned h)
  31 {
  32         row_length = w;
  33         image_height = h;
  34 }
  35
  36 void PixelStore::set_origin(unsigned x, unsigned y, unsigned z)
  37 {
  38         skip_pixels = x;
  39         skip_rows = y;
  40         skip_images = z;
  41 }
  42
  43 void PixelStore::set_alignment(unsigned a)
  44 {
  45         alignment = a;
  46 }
  47
  48 void PixelStore::bind() const
  49 {
  50         if(set_current(this))
  51         {
  52                 glPixelStorei(GL_UNPACK_ROW_LENGTH, row_length);
  53                 glPixelStorei(GL_UNPACK_IMAGE_HEIGHT, image_height);
  54                 glPixelStorei(GL_UNPACK_SKIP_PIXELS, skip_pixels);
  55                 glPixelStorei(GL_UNPACK_SKIP_ROWS, skip_rows);
  56                 glPixelStorei(GL_UNPACK_SKIP_IMAGES, skip_images);
  57                 glPixelStorei(GL_UNPACK_ALIGNMENT, alignment);
  58         }
  59 }
  60
  61 } // namespace GL
  62 } // namespace Msp