git.sesse.net Git - movit/blob - flat_input.cpp

   1 #include <string.h>
   2 #include <assert.h>
   3 #include <GL/glew.h>
   4
   5 #include "effect_util.h"
   6 #include "flat_input.h"
   7 #include "util.h"
   8
   9 FlatInput::FlatInput(ImageFormat image_format, MovitPixelFormat pixel_format, GLenum type, unsigned width, unsigned height)
  10         : image_format(image_format),
  11           pixel_format(pixel_format),
  12           type(type),
  13           pbo(0),
  14           texture_num(0),
  15           needs_update(false),
  16           finalized(false),
  17           output_linear_gamma(false),
  18           needs_mipmaps(false),
  19           width(width),
  20           height(height),
  21           pitch(width),
  22           pixel_data(NULL)
  23 {
  24         assert(type == GL_FLOAT || type == GL_UNSIGNED_BYTE);
  25         register_int("output_linear_gamma", &output_linear_gamma);
  26         register_int("needs_mipmaps", &needs_mipmaps);
  27 }
  28
  29 FlatInput::~FlatInput()
  30 {
  31         if (pbo != 0) {
  32                 glDeleteBuffers(1, &pbo);
  33                 check_error();
  34         }
  35         if (texture_num != 0) {
  36                 glDeleteTextures(1, &texture_num);
  37                 check_error();
  38         }
  39 }
  40
  41 void FlatInput::finalize()
  42 {
  43         // Translate the input format to OpenGL's enums.
  44         GLenum internal_format;
  45         if (type == GL_FLOAT) {
  46                 internal_format = GL_RGBA16F_ARB;
  47         } else if (output_linear_gamma) {
  48                 assert(type == GL_UNSIGNED_BYTE);
  49                 internal_format = GL_SRGB8_ALPHA8;
  50         } else {
  51                 assert(type == GL_UNSIGNED_BYTE);
  52                 internal_format = GL_RGBA8;
  53         }
  54         if (pixel_format == FORMAT_RGB) {
  55                 format = GL_RGB;
  56                 bytes_per_pixel = 3;
  57         } else if (pixel_format == FORMAT_RGBA_PREMULTIPLIED_ALPHA ||
  58                    pixel_format == FORMAT_RGBA_POSTMULTIPLIED_ALPHA) {
  59                 format = GL_RGBA;
  60                 bytes_per_pixel = 4;
  61         } else if (pixel_format == FORMAT_BGR) {
  62                 format = GL_BGR;
  63                 bytes_per_pixel = 3;
  64         } else if (pixel_format == FORMAT_BGRA_PREMULTIPLIED_ALPHA ||
  65                    pixel_format == FORMAT_BGRA_POSTMULTIPLIED_ALPHA) {
  66                 format = GL_BGRA;
  67                 bytes_per_pixel = 4;
  68         } else if (pixel_format == FORMAT_GRAYSCALE) {
  69                 format = GL_LUMINANCE;
  70                 bytes_per_pixel = 1;
  71         } else {
  72                 assert(false);
  73         }
  74         if (type == GL_FLOAT) {
  75                 bytes_per_pixel *= sizeof(float);
  76         }
  77
  78         // Create PBO to hold the texture holding the input image, and then the texture itself.
  79         glGenBuffers(1, &pbo);
  80         check_error();
  81         glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, pbo);
  82         check_error();
  83         glBufferData(GL_PIXEL_UNPACK_BUFFER_ARB, pitch * height * bytes_per_pixel, NULL, GL_STREAM_DRAW);
  84         check_error();
  85         glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 0);
  86         check_error();
  87
  88         glGenTextures(1, &texture_num);
  89         check_error();
  90         glBindTexture(GL_TEXTURE_2D, texture_num);
  91         check_error();
  92         glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
  93         check_error();
  94         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, needs_mipmaps ? GL_LINEAR_MIPMAP_NEAREST : GL_LINEAR);
  95         check_error();
  96         glPixelStorei(GL_UNPACK_ROW_LENGTH, pitch);
  97         check_error();
  98         // Intel/Mesa seems to have a broken glGenerateMipmap() for non-FBO textures, so do it here
  99         // instead of calling glGenerateMipmap().
 100         glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP, needs_mipmaps ? GL_TRUE : GL_FALSE);
 101         check_error();
 102         glTexImage2D(GL_TEXTURE_2D, 0, internal_format, width, height, 0, format, type, NULL);
 103         check_error();
 104         glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
 105         check_error();
 106
 107         needs_update = true;
 108         finalized = true;
 109 }
 110
 111 void FlatInput::set_gl_state(GLuint glsl_program_num, const std::string& prefix, unsigned *sampler_num)
 112 {
 113         glActiveTexture(GL_TEXTURE0 + *sampler_num);
 114         check_error();
 115         glBindTexture(GL_TEXTURE_2D, texture_num);
 116         check_error();
 117
 118         if (needs_update) {
 119                 // Copy the pixel data into the PBO.
 120                 glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, pbo);
 121                 check_error();
 122                 void *mapped_pbo = glMapBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB, GL_WRITE_ONLY);
 123                 memcpy(mapped_pbo, pixel_data, pitch * height * bytes_per_pixel);
 124                 glUnmapBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB);
 125                 check_error();
 126
 127                 // Re-upload the texture from the PBO.
 128                 glPixelStorei(GL_UNPACK_ROW_LENGTH, pitch);
 129                 check_error();
 130                 glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, format, type, BUFFER_OFFSET(0));
 131                 check_error();
 132                 glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
 133                 check_error();
 134                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 135                 check_error();
 136                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 137                 check_error();
 138                 glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 0);
 139                 check_error();
 140
 141                 needs_update = false;
 142         }
 143
 144         // Bind it to a sampler.
 145         set_uniform_int(glsl_program_num, prefix, "tex", *sampler_num);
 146         ++*sampler_num;
 147 }
 148
 149 std::string FlatInput::output_fragment_shader()
 150 {
 151         return read_file("flat_input.frag");
 152 }