diff options
| -rw-r--r-- | main.c | 67 |
1 files changed, 60 insertions, 7 deletions
@@ -13,6 +13,11 @@ // custom SDL_USEREVENT code for timer #define EVENT_CODE_TIMER 0 +typedef struct { + const GLuint type; + const char *src; +} shader_t; + static const float verts[] = { -0.5, 0.5, 0, @@ -20,8 +25,8 @@ verts[] = { 0.0, -0.5, 0, }; -static const char * -vs_src = +static const char +vs_src[] = "#version 320 es\n" "\n" "layout (location = 0) in mediump vec3 pos;\n" @@ -30,8 +35,8 @@ vs_src = " gl_Position = vec4(pos.x, pos.y, pos.z, 1);\n" "}\n"; -static const char * -fs_src = +static const char +fs_src[] = "#version 320 es\n" "\n" "out mediump vec4 color;\n" @@ -42,6 +47,12 @@ fs_src = " color = vec4(0.5f + 0.5 * sin(time * 3.141), 0, 0, 1);\n" "}\n"; +static const shader_t +RENDER_SHADERS[] = { + { GL_VERTEX_SHADER, vs_src }, + { GL_FRAGMENT_SHADER, fs_src }, +}; + static GLuint compile_shader( const GLenum type, @@ -69,6 +80,47 @@ compile_shader( } static GLuint +link_program( + const size_t num_shaders, + const shader_t *shaders +) { + // create program + GLuint r = glCreateProgram(); + + // compile shaders + GLuint ids[128]; + for (size_t i = 0; i < num_shaders; i++) { + // compile shader + ids[i] = compile_shader(shaders[i].type, shaders[i].src); + + // attach shader + glAttachShader(r, ids[i]); + } + + // link program + glLinkProgram(r); + + // check link status + GLint ok; + glGetProgramiv(r, GL_LINK_STATUS, &ok); + if (!ok) { + GLchar log[1024]; + glGetProgramInfoLog(r, sizeof(log), NULL, log); + fprintf(stderr, "Program Link Error: %s\n", log); + exit(EXIT_FAILURE); + } + + // delete shaders + for (size_t i = 0; i < num_shaders; i++) { + glDeleteShader(ids[i]); + } + + // return result + return r; +} + +#if 0 +static GLuint link_render_program( const char * const vs_src, const char * const fs_src @@ -97,13 +149,14 @@ link_render_program( exit(EXIT_FAILURE); } - // delete shaders + // delete shaders glDeleteShader(vs); glDeleteShader(fs); // return result return r; } +#endif /* 0 */ #if 0 static GLuint @@ -114,7 +167,7 @@ link_compute_program( GLuint r = glCreateProgram(); } -#endif +#endif /* 0 */ static void update_viewport( @@ -262,7 +315,7 @@ int main(int argc, char *argv[]) { glBindVertexArray(0); // link program - GLuint prog = link_render_program(vs_src, fs_src); + GLuint prog = link_program(2, RENDER_SHADERS); GLint u_time = glGetUniformLocation(prog, "time"); // init flags |