source/backends/opengl/texture_backend.cpp

   1 #include <msp/gl/extensions/arb_direct_state_access.h>
   2 #include <msp/gl/extensions/arb_texture_swizzle.h>
   3 #include <msp/gl/extensions/ext_framebuffer_object.h>
   4 #include <msp/gl/extensions/khr_debug.h>
   5 #include "device.h"
   6 #include "gl.h"
   7 #include "error.h"
   8 #include "texture.h"
   9 #include "texture_backend.h"
  10
  11 using namespace std;
  12
  13 namespace Msp {
  14 namespace GL {
  15
  16 OpenGLTexture::OpenGLTexture(unsigned t):
  17         target(t)
  18 {
  19         static bool alignment_init = false;
  20         if(!alignment_init)
  21         {
  22                 glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
  23                 alignment_init = true;
  24         }
  25 }
  26
  27 OpenGLTexture::OpenGLTexture(OpenGLTexture &&other):
  28         id(other.id),
  29         target(other.target),
  30         debug_name(move(other.debug_name))
  31 {
  32         other.id = 0;
  33 }
  34
  35 OpenGLTexture::~OpenGLTexture()
  36 {
  37         if(this==Device::get_current().get_state().scratch_texture)
  38                 unbind_scratch();
  39         if(id)
  40                 glDeleteTextures(1, &id);
  41 }
  42
  43 void OpenGLTexture::create()
  44 {
  45         if(id)
  46                 throw invalid_operation("OpenGLTexture::create");
  47         if(ARB_direct_state_access)
  48                 glCreateTextures(target, 1, &id);
  49         else
  50                 glGenTextures(1, &id);
  51
  52 #ifdef DEBUG
  53         if(!debug_name.empty() && KHR_debug)
  54                 glObjectLabel(GL_TEXTURE, id, debug_name.size(), debug_name.c_str());
  55 #endif
  56 }
  57
  58 void OpenGLTexture::require_swizzle()
  59 {
  60         static Require _req(ARB_texture_swizzle);
  61 }
  62
  63 void OpenGLTexture::apply_swizzle()
  64 {
  65         ComponentSwizzle swizzle = static_cast<const Texture *>(this)->swizzle;
  66         if(swizzle==NO_SWIZZLE)
  67                 return;
  68
  69         const int *swizzle_order = get_gl_swizzle(swizzle);
  70         if(get_backend_api()==OPENGL_ES)
  71         {
  72                 set_parameter_i(GL_TEXTURE_SWIZZLE_R, swizzle_order[0]);
  73                 set_parameter_i(GL_TEXTURE_SWIZZLE_G, swizzle_order[1]);
  74                 set_parameter_i(GL_TEXTURE_SWIZZLE_B, swizzle_order[2]);
  75                 set_parameter_i(GL_TEXTURE_SWIZZLE_A, swizzle_order[3]);
  76         }
  77         else
  78         {
  79                 if(ARB_direct_state_access)
  80                         glTextureParameteriv(id, GL_TEXTURE_SWIZZLE_RGBA, swizzle_order);
  81                 else
  82                         glTexParameteriv(target, GL_TEXTURE_SWIZZLE_RGBA, swizzle_order);
  83         }
  84 }
  85
  86 void OpenGLTexture::set_parameter_i(unsigned param, int value) const
  87 {
  88         if(ARB_direct_state_access)
  89                 glTextureParameteri(id, param, value);
  90         else
  91                 glTexParameteri(target, param, value);
  92 }
  93
  94 void OpenGLTexture::generate_mipmap()
  95 {
  96         // glGenerateMipmap is defined here
  97         static Require _req(EXT_framebuffer_object);
  98
  99         if(ARB_direct_state_access)
 100                 glGenerateTextureMipmap(id);
 101         else
 102         {
 103                 bind_scratch();
 104                 glGenerateMipmap(target);
 105         }
 106 }
 107
 108 void OpenGLTexture::set_debug_name(const string &name)
 109 {
 110 #ifdef DEBUG
 111         debug_name = name;
 112         if(id && KHR_debug)
 113                 glObjectLabel(GL_TEXTURE, id, name.size(), name.c_str());
 114 #else
 115         (void)name;
 116 #endif
 117 }
 118
 119 void OpenGLTexture::bind_scratch()
 120 {
 121         const OpenGLTexture *&scratch_binding = Device::get_current().get_state().scratch_texture;
 122         if(!scratch_binding)
 123                 glActiveTexture(GL_TEXTURE0);
 124         if(scratch_binding!=this)
 125         {
 126                 if(scratch_binding && scratch_binding->target!=target)
 127                         glBindTexture(scratch_binding->target, 0);
 128                 glBindTexture(target, id);
 129                 scratch_binding = this;
 130         }
 131 }
 132
 133 void OpenGLTexture::unbind_scratch()
 134 {
 135         const OpenGLTexture *&scratch_binding = Device::get_current().get_state().scratch_texture;
 136         if(scratch_binding)
 137         {
 138                 glBindTexture(scratch_binding->target, 0);
 139                 scratch_binding = 0;
 140         }
 141 }
 142
 143 } // namespace GL
 144 } // namespace Msp