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

   1 #include <GL/glew.h>
   2
   3 #include "slice_effect.h"
   4 #include "effect_util.h"
   5 #include "util.h"
   6
   7 using namespace std;
   8
   9 namespace movit {
  10
  11 SliceEffect::SliceEffect()
  12 {
  13         register_int("input_slice_size", &input_slice_size);
  14         register_int("output_slice_size", &output_slice_size);
  15         register_int("direction", (int *)&direction);
  16 }
  17
  18 string SliceEffect::output_fragment_shader()
  19 {
  20         char buf[256];
  21         sprintf(buf, "#define DIRECTION_VERTICAL %d\n", (direction == VERTICAL));
  22         return buf + read_file("slice_effect.frag");
  23 }
  24
  25 void SliceEffect::inform_input_size(unsigned input_num, unsigned width, unsigned height)
  26 {
  27         assert(input_num == 0);
  28         input_width = width;
  29         input_height = height;
  30 }
  31
  32 void SliceEffect::get_output_size(unsigned *width, unsigned *height,
  33                                   unsigned *virtual_width, unsigned *virtual_height) const
  34 {
  35         if (direction == HORIZONTAL) {
  36                 *width = div_round_up(input_width, input_slice_size) * output_slice_size;
  37                 *height = input_height;
  38         } else {
  39                 *width = input_width;
  40                 *height = div_round_up(input_height, input_slice_size) * output_slice_size;
  41         }
  42         *virtual_width = *width;
  43         *virtual_height = *height;
  44 }
  45
  46 void SliceEffect::set_gl_state(GLuint glsl_program_num, const string &prefix, unsigned *sampler_num)
  47 {
  48         Effect::set_gl_state(glsl_program_num, prefix, sampler_num);
  49
  50         unsigned output_width, output_height;
  51         get_output_size(&output_width, &output_height, &output_width, &output_height);
  52
  53         if (direction == HORIZONTAL) {
  54                 set_uniform_float(glsl_program_num, prefix, "output_coord_to_slice_num", float(output_width) / float(output_slice_size));
  55                 set_uniform_float(glsl_program_num, prefix, "slice_num_to_input_coord", float(input_slice_size) / float(input_width));
  56                 set_uniform_float(glsl_program_num, prefix, "slice_offset_to_input_coord", float(output_slice_size) / float(input_width));
  57         } else {
  58                 set_uniform_float(glsl_program_num, prefix, "output_coord_to_slice_num", float(output_height) / float(output_slice_size));
  59                 set_uniform_float(glsl_program_num, prefix, "slice_num_to_input_coord", float(input_slice_size) / float(input_height));
  60                 set_uniform_float(glsl_program_num, prefix, "slice_offset_to_input_coord", float(output_slice_size) / float(input_height));
  61         }
  62
  63         // Normalized coordinates could potentially cause blurring of the
  64         // image; it's not critical, but we have set changes_output_size()
  65         // and needs_texture_bounce(), so simply turning off the interpolation
  66         // is allowed.
  67         assert(*sampler_num == 1);
  68         glActiveTexture(GL_TEXTURE0);
  69         check_error();
  70         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
  71         check_error();
  72         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
  73         check_error();
  74 }
  75
  76 }  // namespace movit