librashader/include/README.md
chyyran cff4f650c9 ld: add a flag to check if the instance is loaded
Also explicitly create function pointers to NULL, otherwise
null instance is technically unsound to call.

Practically if the create function is unloaded, so will the frame
function, but we should be consistent with the safety model.
2023-02-11 16:40:33 -05:00

1.6 KiB

librashader C headers

The librashader C headers are unlike the implementations, explicitly licensed under the MIT license.

They are provided for easy integration of librashader in a multi-target C or C++ project that may not have the necessary hardware or APIs available required for all supported runtimes.

librashader.h can be depended upon to link with librashader.dll or librashader.so if you wish to link with librashader.

An easier alternative is to use the librashader_ld.h header library to load function pointers from any librashader.dll or librashader.so implementation in the search path. You should customize this header file to remove support for any runtimes you do not need.

Usage

A basic example of using librashader_ld.h to load a shader preset.

#include "librashader_ld.h"

libra_gl_filter_chain_t load_gl_filter_chain(libra_gl_loader_t opengl, const char *preset_path) {
  libra_instance_t librashader = librashader_load_instance();
  
  if (!librashader.instance_loaded) {
    std::cout << "Could not load librashader\n";
    return NULL;
  }
  
  libra_shader_preset_t preset;
  libra_error_t error = librashader.preset_create(preset_path, &preset);
  if (error != NULL) {
    std::cout << "Could not load preset\n";
    return NULL;
  }

  // OpenGL runtime needs to be initialized.
  if (librashader.gl_init_context(opengl) != NULL) {
    std::cout << "Could not initialize OpenGL context\n";
    return NULL;
  }
  
  libra_gl_filter_chain_t chain;
  if (librashader.gl_filter_chain_create(&preset, NULL, &chain) {
    std::cout << "Could not create OpenGL filter chain\n";
  }
  return chain;
}