D, Derelict2, and OpenGL

[David]

Am 20.04.2012 00:34, schrieb Stephen Jones:
> In the same vein, I have getting nothing on the screen when there should
> be rendered a red triangle. The vertex positions are those used by
> McKeeson http://www.arcsynthesis.org/gltut/, being in ndc fall within
> the frustum. The code for setting up vao and shaders is:
>
> module ShaderHub;
>
> import std.stdio;
> import std.string;
> import derelict.opengl3.gl3;
>
> class ShaderHub{
> private bool ok=true;
> private GLuint shad=0, vshad=0, fshad=0;
> private int voff=0;
> private GLuint vbo=0, vao=0;
> const float[] v = [ 0.75f, 0.75f, 0.0f, 1.0f,
> 0.75f, -0.75f, 0.0f, 1.0f,
> -0.75f, -0.75f, 0.0f, 1.0f];
>
> public this(){
> immutable string vshader = `
> #version 330
> layout(location = 1) in vec4 pos;
> void main(void)
> {
> gl_Position = pos;
> }
> `;
>
> immutable string fshader = `
> #version 330
> void main(void)
> {
> gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
> }
> `;
>
> shad=glCreateProgram();
> if(shad==0){
> writeln("Error: GL did not assigh main shader program id");
> ok=false;
> }
>
> vshad=glCreateShader(GL_VERTEX_SHADER);
> const char *vptr=toStringz(vshader);
> glShaderSource(vshad, 1, &vptr, null);
> glCompileShader(vshad);
> int status, len;
> glGetShaderiv(vshad, GL_COMPILE_STATUS, &status);
> if(status==GL_FALSE){
> glGetShaderiv(vshad, GL_INFO_LOG_LENGTH, &len);
> char[] error=new char[len];
> glGetShaderInfoLog(vshad, len, null, cast(char*)error);
> writeln(error);
> ok=false;
> }
>
> fshad=glCreateShader(GL_FRAGMENT_SHADER);
> const char *fptr=toStringz(fshader);
> glShaderSource(fshad, 1, &fptr, null);
> glCompileShader(fshad);
> glGetShaderiv(vshad, GL_COMPILE_STATUS, &status);
> if(status==GL_FALSE){
> glGetShaderiv(fshad, GL_INFO_LOG_LENGTH, &len);
> char[] error=new char[len];
> glGetShaderInfoLog(fshad, len, null, cast(char*)error);
> writeln(error);
> ok=false;
> }
>
> glAttachShader(shad, vshad);
> glAttachShader(shad, fshad);
> glLinkProgram(shad);
> glGetShaderiv(shad, GL_LINK_STATUS, &status);
> if(status==GL_FALSE){
> glGetShaderiv(shad, GL_INFO_LOG_LENGTH, &len);
> char[] error=new char[len];
> glGetShaderInfoLog(shad, len, null, cast(char*)error);
> writeln(error);
> ok=false;
> }
>
>
> glGenVertexArrays(1, &vao);
> if(vao<1){
> writeln("Error: GL failed to assign vao id");
> ok=false;
> }
> glBindVertexArray(vao);
>
> glGenBuffers(1, &vbo);
> if(vbo<1){
> writeln("Error: GL failed to assign vbo id");
> ok=false;
> }
> glBindBuffer(GL_ARRAY_BUFFER, vbo);
> glBufferData(GL_ARRAY_BUFFER, v.length * GL_FLOAT.sizeof, &v[0],
> GL_STATIC_DRAW);
> glEnableVertexAttribArray(1);
> glVertexAttribPointer(1, 4, GL_FLOAT, GL_FALSE, 0, cast(void*)voff);
>
> glBindBuffer(GL_ARRAY_BUFFER, 0);
> glBindVertexArray(0);
> }
>
> public void draw(){
> glUseProgram(shad);
>
> writeln(glGetAttribLocation(shad, "pos"));//prints 1
>
> glBindVertexArray(vao);
> glDrawArrays(GL_TRIANGLES, 0, 6);
> glBindVertexArray(0);
>
>
> glUseProgram(0);
> }
> }
>
> //__________________________________________________________________
>
> the code for setting up openGL3 is:
>
>
> import std.stdio;
> import derelict.sdl2.sdl;
> import derelict.opengl3.gl3;
>
> import EventHub;
> import ExposeApp;
>
> pragma(lib, "DerelictUtil.lib");
> pragma(lib, "DerelictSDL2.lib");
> pragma(lib, "DerelictGL3.lib");
>
>
> class App{
> private ExposeApp funcPtrs;
> private EventHub ehub;
> private SDL_Window *win;
> private SDL_GLContext context;
> private int w=600, h=480, fov=55;
> private bool running=true;
>
> public this(){
> if(!initSDL()){
> writeln("Error initializing SDL");
> SDL_Quit();
> }
> initGL();
>
> funcPtrs=new ExposeApp();
> funcPtrs.stop=&stopLoop;
> funcPtrs.grabMouse=&grabMouse;
> funcPtrs.releaseMouse=&releaseMouse;
> ehub=new EventHub(funcPtrs);
>
>
> while(running){
> glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
>
> ehub.tick();
>
> SDL_GL_SwapWindow(win);
> }
>
>
> SDL_GL_DeleteContext(context);
> SDL_DestroyWindow(win);
> SDL_Quit();
> }
>
> private void stopLoop(){
> running=false;
> }
> private void grabMouse(){
> SDL_ShowCursor(SDL_DISABLE);
> SDL_SetWindowGrab(win, SDL_TRUE);
> }
> private void releaseMouse(){
> SDL_ShowCursor(SDL_ENABLE);
> SDL_SetWindowGrab(win, SDL_FALSE);
> }
> private bool initSDL(){
> if(SDL_Init(SDL_INIT_VIDEO)< 0){
> writefln("Error initializing SDL");
> SDL_Quit();
> return false;
> }
>
> SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
> SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2);
> SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
> SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
>
> win=SDL_CreateWindow("3Doodle", SDL_WINDOWPOS_CENTERED,
> SDL_WINDOWPOS_CENTERED, w, h, SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN);
> if(!win){
> writefln("Error creating SDL window");
> SDL_Quit();
> return false;
> }
>
> context=SDL_GL_CreateContext(win);
> SDL_GL_SetSwapInterval(1);
>
> DerelictGL3.reload();
>
> return true;
> }
> private void initGL(){
> resize(w, h);
>
> glEnable(GL_DEPTH_TEST);
> glEnable(GL_CULL_FACE);
>
> glDepthFunc(GL_LEQUAL);
>
> glClearColor(0.0, 0.0, 0.0, 1.0);
> glClearDepth(1.0);
>
> glCullFace(GL_BACK);
> glFrontFace(GL_CCW);
>
> }
> private void resize(int w, int h){
> //this will contain the makings of the projection matrix, which we go
> into next tut
> glViewport(0, 0, w, h);
> }
> }
>
>
> void main(){
> try{
> DerelictSDL2.load();
> }catch(Exception e){
> writeln("Error loading SDL2 lib");
> }
> try{
> DerelictGL3.load();
> }catch(Exception e){
> writeln("Error loading GL3 lib");
> }
>
> App a=new App();
> }
>
>
> Any help would be great.

Question on Stackoverflow: 
http://stackoverflow.com/questions/10236529/why-doesnt-derelictgl3-draw-anything

If you ask here, pls open a new "Thread", appending just confuses people 
like me.