source/backends/opengl/texture1d_backend.cpp

   1 #include <msp/gl/extensions/arb_direct_state_access.h>
   2 #include <msp/gl/extensions/arb_texture_storage.h>
   3 #include <msp/gl/extensions/msp_texture1d.h>
   4 #include "gl.h"
   5 #include "texture1d.h"
   6 #include "texture1d_backend.h"
   7
   8 namespace Msp {
   9 namespace GL {
  10
  11 OpenGLTexture1D::OpenGLTexture1D():
  12         Texture(GL_TEXTURE_1D)
  13 {
  14         static Require _req(MSP_texture1D);
  15 }
  16
  17 void OpenGLTexture1D::allocate()
  18 {
  19         const Texture1D &self = *static_cast<const Texture1D *>(this);
  20
  21         if(!id)
  22                 create();
  23
  24         GLenum gl_fmt = get_gl_pixelformat(storage_fmt);
  25         if(ARB_texture_storage)
  26         {
  27                 if(ARB_direct_state_access)
  28                         glTextureStorage1D(id, n_levels, gl_fmt, self.width);
  29                 else
  30                 {
  31                         bind_scratch();
  32                         glTexStorage1D(target, n_levels, gl_fmt, self.width);
  33                 }
  34         }
  35         else
  36         {
  37                 bind_scratch();
  38                 glTexParameteri(target, GL_TEXTURE_MAX_LEVEL, n_levels-1);
  39                 GLenum comp = get_gl_components(get_components(storage_fmt));
  40                 GLenum type = get_gl_type(get_component_type(storage_fmt));
  41                 for(unsigned i=0; i<n_levels; ++i)
  42                 {
  43                         unsigned lv_size = self.get_level_size(i);
  44                         glTexImage1D(target, i, gl_fmt, lv_size, 0, comp, type, 0);
  45                 }
  46         }
  47
  48         apply_swizzle();
  49 }
  50
  51 void OpenGLTexture1D::sub_image(unsigned level, int x, unsigned wd, const void *data)
  52 {
  53         GLenum comp = get_gl_components(get_components(storage_fmt));
  54         GLenum type = get_gl_type(get_component_type(storage_fmt));
  55         if(ARB_direct_state_access)
  56                 glTextureSubImage1D(id, level, x, wd, comp, type, data);
  57         else
  58         {
  59                 bind_scratch();
  60                 glTexSubImage1D(target, level, x, wd, comp, type, data);
  61         }
  62 }
  63
  64 size_t OpenGLTexture1D::get_data_size() const
  65 {
  66         if(!id)
  67                 return 0;
  68
  69         const Texture1D &self = *static_cast<const Texture1D *>(this);
  70
  71         size_t level_size = self.width*get_pixel_size(storage_fmt);
  72         size_t total_size = level_size;
  73         for(unsigned i=0; i<n_levels; ++i, level_size>>=2)
  74                 total_size += level_size;
  75         return total_size;
  76 }
  77
  78 } // namespace GL
  79 } // namespace Msp