Add support for multiple shader models.

[movit] / util.cpp

diff --git a/util.cpp b/util.cpp
index cd820bc74afe3d7ee8314ee1d47da82bb33cf55a..01787f013e0a4c70817be2ccf49743cddb7bd254 100644 (file)
--- a/util.cpp
+++ b/util.cpp
@@ -9,6 +9,14 @@
 #include "init.h"
 #include "util.h"
 
+#if defined(__DARWIN__)
+#include <OpenGL/OpenGL.h>
+#elif defined(WIN32)
+#include <epoxy/wgl.h>
+#else
+#include <epoxy/glx.h>
+#endif
+
 using namespace std;
 
 namespace movit {
@@ -88,6 +96,19 @@ string read_file(const string &filename)
        return string(buf, len);
 }
 
+string read_version_dependent_file(const string &base, const string &extension)
+{
+       if (movit_shader_model == MOVIT_GLSL_110) {
+               return read_file(base + "." + extension);
+       } else if (movit_shader_model == MOVIT_GLSL_130) {
+               return read_file(base + ".130." + extension);
+       } else if (movit_shader_model == MOVIT_ESSL_300) {
+               return read_file(base + ".300es." + extension);
+       } else {
+               assert(false);
+       }
+}
+
 GLuint compile_shader(const string &shader_src, GLenum type)
 {
        GLuint obj = glCreateShader(type);
@@ -215,4 +236,33 @@ void cleanup_vertex_attribute(GLuint glsl_program_num, const string &attribute_n
        check_error();
 }
 
+unsigned div_round_up(unsigned a, unsigned b)
+{
+       return (a + b - 1) / b;
+}
+
+// Algorithm from http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2.
+unsigned next_power_of_two(unsigned v)
+{
+       v--;
+       v |= v >> 1;
+       v |= v >> 2;
+       v |= v >> 4;
+       v |= v >> 8;
+       v |= v >> 16;
+       v++;
+       return v;
+}
+
+void *get_gl_context_identifier()
+{
+#if defined(__DARWIN__)
+       return (void *)CGLGetCurrentContext();
+#elif defined(WIN32)
+       return (void *)wglGetCurrentContext();
+#else
+       return (void *)glXGetCurrentContext();
+#endif
+}
+
 }  // namespace movit