shader_kit_debug.cpp

 
#include <cstdio>
#include <cstring>
 
#include <chrono>
 
#include "glcore.h"
#include "window.h"
#include "files.h"
 
#include "program.h"
#include "uniforms.h"
 
#include "texture.h"
#include "mesh.h"
#include "wavefront.h"
 
#include "vec.h"
#include "mat.h"
#include "orbiter.h"
 
#include "text.h"
#include "widgets.h"
 
 
// program
const char *program_filename;
GLuint program;
 
// affichage des erreurs de compilation
std::string program_log;
int program_area;
bool program_failed;
 
// mesh, si charge...
const char *mesh_filename;
Mesh mesh;
Point mesh_pmin;
Point mesh_pmax;
int vertex_count;
 
GLuint vao;
 
// textures
std::vector<const char *> texture_filenames;
std::vector<GLuint> textures;
 
// affichage
bool wireframe= false;
int debug= 0;
int debug_capture= 0;
int debug_mode= 1;
 
// camera
Orbiter mesh_camera;
 
// ui
Widgets widgets;
 
// mode debug
GLuint debug_framebuffer= 0;
GLuint debug_color;
GLuint debug_depth;
GLuint debug_position;
GLuint debug_normal;
GLuint debug_data;
 
GLuint debug_program= 0;
GLuint debug_wireframe_program= 0;
 
Orbiter debug_camera;
Transform debug_mvpi_inv;
 
 
GLuint make_debug_framebuffer( const int w, const int h )
{
    glGenFramebuffers(1, &debug_framebuffer);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, debug_framebuffer);
    
    debug_depth= make_depth_texture(0, w, h);
    debug_color= make_vec4_texture(0, w, h);
    debug_position= make_vec4_texture(0, w, h);
    debug_normal= make_vec4_texture(0, w, h);
    debug_data= make_vec4_texture(0, w, h);
    
    glFramebufferTexture(GL_DRAW_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, debug_depth, /* mipmap */ 0);
    glFramebufferTexture(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, debug_color, /* mipmap */ 0);
    glFramebufferTexture(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT1, debug_position, /* mipmap */ 0);
    glFramebufferTexture(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT2, debug_normal, /* mipmap */ 0);
    glFramebufferTexture(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT3, debug_data, /* mipmap */ 0);
    
    GLenum buffers[]= { GL_COLOR_ATTACHMENT0, GL_COLOR_ATTACHMENT1, GL_COLOR_ATTACHMENT2, GL_COLOR_ATTACHMENT3 };
    glDrawBuffers(4, buffers);
    
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
    glBindTexture(GL_TEXTURE_2D, 0);
    
    return debug_framebuffer;
}
 
void clear_debug_framebuffer( )
{
    float one[]= { 1 };
    glClearBufferfv(GL_DEPTH, 0, one);
    
    float zero[]= { 0, 0, 0, 0 };
    glClearBufferfv(GL_COLOR, 0, zero);
    glClearBufferfv(GL_COLOR, 1, zero);
    glClearBufferfv(GL_COLOR, 2, zero);
    glClearBufferfv(GL_COLOR, 3, zero);
}
 
void release_debug_framebuffer( )
{
    glDeleteTextures(1, &debug_depth);
    glDeleteTextures(1, &debug_color);
    glDeleteTextures(1, &debug_position);
    glDeleteTextures(1, &debug_normal);
    glDeleteTextures(1, &debug_data);
    glDeleteFramebuffers(1, &debug_framebuffer);
}
 
 
vec4 read_debug( const int x, const int y, const GLenum attach )
{
    glReadBuffer(attach);
    
    vec4 tmp[16];
    glReadPixels(x - 2, y - 2, 4, 4, GL_RGBA, GL_FLOAT, tmp);
    
    // trouver un pixel avec des donnees
    for(int i= 0; i < 16; i++)
        if(tmp[i].x || tmp[i].y || tmp[i].z || tmp[i].w)
            return tmp[i];
    
    return vec4(0, 0, 0, 0);
}
 
vec4 read_debug_color( const int x, const int y )
{
    return read_debug(x, y, GL_COLOR_ATTACHMENT0);
}
vec4 read_debug_position( const int x, const int y )
{
    return read_debug(x, y, GL_COLOR_ATTACHMENT1);
}
vec4 read_debug_normal( const int x, const int y )
{
    return read_debug(x, y, GL_COLOR_ATTACHMENT2);
}
vec4 read_debug_data( const int x, const int y )
{
    return read_debug(x, y, GL_COLOR_ATTACHMENT3);
}
 
float read_depth( const int x, const int y )
{
    glReadBuffer(GL_BACK);
    
    float tmp[16];
    glReadPixels(x - 2, y - 2, 4, 4, GL_DEPTH_COMPONENT, GL_FLOAT, tmp);
    
    // trouver un pixel avec des donnees
    for(int i= 0; i < 16; i++)
        if(tmp[i] != 1) // si zbufffer == 1, pas de geometrie dessinee sur le pixel...
            return tmp[i];
    
    return -1;
}
 
// application
size_t last_load= 0;
void reload_program( )
{
    if(program == 0)
        program= read_program(program_filename);
    else
        reload_program(program);
    
    // conserve la date du fichier
    last_load= timestamp(program_filename);
    
    // recupere les erreurs, si necessaire
    program_area= program_format_errors(program, program_log);
    
    program_failed= program_errors( program );
    if(program_failed)
        printf("[boom]\n%s\n", program_log.c_str());
}
 
 
// cherche un fichier avec l'extension ext dans les options
const char *option_find( std::vector<const char *>& options, const char *ext )
{
    for(unsigned int i= 0; i < (unsigned int) options.size() ; i++)
    {
        if(options[i] != nullptr && std::string(options[i]).rfind(ext) != std::string::npos)
        {
            const char *option= options[i];
            options[i]= nullptr;
            return option;
        }
    }
    
    return nullptr;
}

int init( std::vector<const char *>& options )
{
    widgets= create_widgets();
    mesh_camera= Orbiter();
    
    program= 0;
    const char *option;
    option= option_find(options, ".glsl");
    if(option != nullptr)
    {
        program_filename= option;
        reload_program();
    }
    
    vao= 0;
    mesh_pmin= Point(normalize(Vector(-1, -1, 0)) * 2.5f);
    mesh_pmax= Point(normalize(Vector( 1,  1, 0)) * 2.5f);
    
    option= option_find(options, ".obj");
    if(option != nullptr)
    {
        mesh= read_mesh(option);
        if(mesh.vertex_count() > 0)
        {
            mesh_filename= option;
            
            vao= mesh.create_buffers(mesh.has_texcoord(), mesh.has_normal(), mesh.has_color(), mesh.has_material_index());
            vertex_count= mesh.vertex_count();
            
            mesh.bounds(mesh_pmin, mesh_pmax);
            mesh_camera.lookat(mesh_pmin, mesh_pmax);
        }
        
        // ou generer une erreur ? 
    }
    
    if(vao == 0)
    {
        glGenVertexArrays(1, &vao);
        vertex_count= 3;
    }
    
    // charge les textures, si necessaire
    for(int i= 0; i < int(options.size()); i++)
    {
        if(options[i] == nullptr)
            continue;
        
        GLuint texture= read_texture(0, options[i]);
        if(texture > 0)
        {
            texture_filenames.push_back(options[i]);
            textures.push_back(texture);
        }
    }
    
    // debug
    debug_wireframe_program= read_program( smart_path("data/shaders/debug_wireframe.glsl") );
    program_print_errors(debug_wireframe_program);
    debug_program= read_program( smart_path("data/shaders/debug.glsl") );
    program_print_errors(debug_program);
    make_debug_framebuffer(window_width(), window_height());
    
    // nettoyage
    glUseProgram(0);
    glBindTexture(GL_TEXTURE_2D, 0);
    glBindVertexArray(0);
    glBindBuffer(GL_ARRAY_BUFFER, 0);
    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
    
    // etat openGL par defaut
    glClearColor(0.2f, 0.2f, 0.2f, 1.f);
    glClearDepth(1.f);
    
    glCullFace(GL_BACK);
    glFrontFace(GL_CCW);
    //~ glEnable(GL_CULL_FACE); // n'affiche que les faces correctement orientees...
    glDisable(GL_CULL_FACE);    // les faces mal orientees sont affichees avec des hachures oranges...
    
    glDepthFunc(GL_LESS);
    glEnable(GL_DEPTH_TEST);
    
    return 0;    
}
 
int quit( )
{
    // detruit les objets openGL
    release_widgets(widgets);
    release_program(program);
    mesh.release();
    
    glDeleteTextures(textures.size(), textures.data());
    return 0;
}
 
int draw( void )
{
    // active / desactive le mode debug
    if(key_state('d'))
    {
        clear_key_state('d');
        debug= (debug +1) %2;
        
        if(debug)
        {
            // capture le rendu...
            debug_capture= 1;
            debug_camera= mesh_camera;
        }
        else
            mesh_camera= debug_camera;
    }
    
    if(wireframe && !debug)
    {
        //~ glClearColor(1, 1, 1, 1);
        glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
        glLineWidth(2);
    }
    else
    {
        //~ glClearColor(0.2f, 0.2f, 0.2f, 1);
        glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
    }
    
    // effacer l'image
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    
    // verification de la date du fichier source des shaders...
    static float last_time= 0;
    // toutes les secondes, ca suffit, pas tres malin de le faire 60 fois par seconde...
    if(global_time() > last_time + 400)
    {
        if(timestamp(program_filename) != last_load)
        {
            // date modifiee, recharger les sources et recompiler...
            reload_program();
        
            // capture l'execution de la nouvelle version du shader...
            if(debug)
                debug_capture= 1; 
        }
        
        // attends le chargement et la compilation des shaders... au cas ou ce soit plus long qu'une seconde...
        // (oui ca arrive...)
        last_time= global_time();
    }
    
    if(key_state('r'))
    {
        clear_key_state('r');
        reload_program();
    }
 
    // controle camera
    Orbiter& camera= debug ? debug_camera : mesh_camera;
    
    // recupere les mouvements de la souris
    int mx, my;
    unsigned int mb= SDL_GetRelativeMouseState(&mx, &my);
    int mousex, mousey;
    SDL_GetMouseState(&mousex, &mousey);
    
    // deplace la camera
    if(mb & SDL_BUTTON(1))
        camera.rotation(mx, my);      // tourne autour de l'objet
    else if(mb & SDL_BUTTON(3))
        camera.translation((float) mx / (float) window_width(), (float) my / (float) window_height()); // deplace le point de rotation
    else if(mb & SDL_BUTTON(2))
        camera.move(mx);           // approche / eloigne l'objet
    
    SDL_MouseWheelEvent wheel= wheel_event();
    if(wheel.y != 0)
    {
        clear_wheel_event();
        camera.move(8.f * wheel.y);  // approche / eloigne l'objet
    }
    
    // etat 
    static float time= 0;
    static int frame= 0;
    static int video= 0;
    static int freeze= 0;
    static int reset_camera= 0;
    static int copy_camera= 0;
    static int paste_camera= 0;
    
    // recupere les transformations
    Transform model= Identity();
    Transform view= camera.view();
    Transform projection= camera.projection(window_width(), window_height(), 45);
    Transform viewport= Viewport(window_width(), window_height());
    
    Transform mvp= projection * view * model;
    Transform mvpInv= Inverse(mvp);
    Transform mv= model * view;
    
    // temps
    if(key_state('t'))
    {
        clear_key_state('t');
        freeze= (freeze+1) % 2;
    }
    if(freeze == 0)
        time= global_time();
    
    // affiche l'objet, ou pas si le shader n'est pas compile...
    if(!program_failed)
    {
        if(key_state('w'))
        {
            clear_key_state('w');
            wireframe= !wireframe;
        }
        
        if(debug && !debug_capture)
        {
            glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
            glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
            
            glBindVertexArray(vao);
            glUseProgram(debug_program);
            
            int mode= debug_mode;
            if(debug_mode == 4) // triangles
                mode= 1;  // affiche la couleur en plus de dessiner les triangles...
            program_uniform(debug_program, "mode", mode);
            
            program_uniform(debug_program, "viewport", vec2(window_width(), window_height()));
            program_uniform(debug_program, "mvpMatrix", mvp * debug_mvpi_inv);
            program_uniform(debug_program, "mvMatrix", mv * debug_mvpi_inv);
            
            program_use_texture(debug_program, "zbuffer", 0, debug_depth);
            program_use_texture(debug_program, "color", 1, debug_color);
            program_use_texture(debug_program, "position", 2, debug_position);
            program_use_texture(debug_program, "normal", 3, debug_normal);
            program_use_texture(debug_program, "data", 4, debug_data);
            
            glPointSize(3.5f);
            glDrawArrays(GL_POINTS, 0, window_width() * window_height());
            
            if(debug_mode == 4)
            {
                // dessine aussi les aretes des triangles
                glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
                
                glUseProgram(debug_wireframe_program);
                program_uniform(debug_wireframe_program, "mvpMatrix", mvp);
                
                glLineWidth(2);
                glDrawArrays(GL_TRIANGLES, 0, vertex_count);
            }
        }
        else
        {
            if(debug_capture)
            {
                debug_capture= 0;       // une seule capture suffit...
                
                // prepare le debug
                glBindFramebuffer(GL_DRAW_FRAMEBUFFER, debug_framebuffer);
                clear_debug_framebuffer();
                
                debug_mvpi_inv= Inverse(viewport * mvp);
            }
            
            glBindVertexArray(vao);
            glUseProgram(program);
            
            // affecte une valeur aux uniforms
            // transformations standards
            program_uniform(program, "modelMatrix", model);
            program_uniform(program, "modelInvMatrix", model.inverse());
            program_uniform(program, "viewMatrix", view);
            program_uniform(program, "viewInvMatrix", view.inverse());
            program_uniform(program, "projectionMatrix", projection);
            program_uniform(program, "projectionInvMatrix", projection.inverse());
            program_uniform(program, "viewportMatrix", viewport);
            program_uniform(program, "viewportInvMatrix", viewport.inverse());
            
            program_uniform(program, "mvpMatrix", mvp);
            program_uniform(program, "mvpInvMatrix", mvpInv);
            
            program_uniform(program, "mvMatrix", mv);
            program_uniform(program, "mvInvMatrix", mv.inverse());
            program_uniform(program, "normalMatrix", mv.normal());
            
            // interactions
            program_uniform(program, "viewport", vec2(window_width(), window_height()));
            program_uniform(program, "time", time);
            program_uniform(program, "motion", vec3(mx, my, mb & SDL_BUTTON(1)));
            program_uniform(program, "mouse", vec3(mousex, window_height() - mousey -1, mb & SDL_BUTTON(1)));
            
            // textures
            for(int i= 0; i < int(textures.size()); i++)
            {
                char uniform[1024];
                sprintf(uniform, "texture%d", i);
                program_use_texture(program, uniform, i, textures[i]);
            }
            
            // go
            glDrawArrays(GL_TRIANGLES, 0, vertex_count);
        }
    }
    
    
    // affiche les infos...
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
    glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
    
    begin(widgets);
    if(program_failed)
    {
        // interface erreurs...
        label(widgets, "[error] program '%s'", program_filename);
        begin_line(widgets);
        text_area(widgets, 20, program_log.c_str(), program_area);
    }
    else if(debug)
    {
        // interface debug...
        button(widgets, "[d] debug", debug);
        
        // reprojette le pixel sous la souris dans le point de vue capture...
        glBindFramebuffer(GL_READ_FRAMEBUFFER, 0);
        float x= mousex + 0.5f;
        float y= window_height() - mousey -1 + 0.5f;
        float z= read_depth(x, y);
        if(z > 0)
        {
            Transform m= Inverse(viewport * mvp * debug_mvpi_inv);
            Point debug_fragment= m( Point(x, y, z) );
            
            // relit les infos du fragment...
            glBindFramebuffer(GL_READ_FRAMEBUFFER, debug_framebuffer);
            vec4 position= read_debug_position(debug_fragment.x, debug_fragment.y);
            vec4 color= read_debug_color(debug_fragment.x, debug_fragment.y);
            vec4 normal= read_debug_normal(debug_fragment.x, debug_fragment.y);
            vec4 data= read_debug_data(debug_fragment.x, debug_fragment.y);
            
            begin_line(widgets);
            label(widgets, "debug (%f, %f, %f)", x, y, z);
            
            begin_line(widgets);
            select(widgets, "draw position", 0, debug_mode);
            label(widgets, "(%f, %f, %f, %f)", position.x, position.y, position.z, position.w);
            
            begin_line(widgets);
            select(widgets, "draw color   ", 1, debug_mode);
            label(widgets, "(%f, %f, %f, %f)", color.x, color.y, color.z, color.w);
            
            begin_line(widgets);
            select(widgets, "draw normal  ", 2, debug_mode);
            label(widgets, "(%f, %f, %f)", normal.x, normal.y, normal.z);
            
            begin_line(widgets);
            select(widgets, "draw data    ", 3, debug_mode);
            label(widgets, "(%f, %f, %f, %f)", data.x, data.y, data.z, data.w);
 
            begin_line(widgets);
            select(widgets, "draw triangles", 4, debug_mode);
            
            // copie une vignette de la capture...
            glReadBuffer(GL_COLOR_ATTACHMENT0);
            glBlitFramebuffer(debug_fragment.x -16, debug_fragment.y -16, debug_fragment.x +16, debug_fragment.y +16,  
                window_width() -256, window_height() -256, window_width(), window_height(), 
                GL_COLOR_BUFFER_BIT, GL_NEAREST);
        }
        else    // pas de capture sur le pixel
        {
            begin_line(widgets);
            label(widgets, "debug (%f, %f)", x, y);
            
            begin_line(widgets);
            select(widgets, "draw position", 0, debug_mode);
            
            begin_line(widgets);
            select(widgets, "draw color   ", 1, debug_mode);
            
            begin_line(widgets);
            select(widgets, "draw normal  ", 2, debug_mode);
            
            begin_line(widgets);
            select(widgets, "draw data    ", 3, debug_mode);
            
            begin_line(widgets);
            select(widgets, "draw triangles", 4, debug_mode);
        }
    }
    else
    {
        // interface standard...
        button(widgets, "[d] debug", debug);
        button(widgets, "[s] screenshot ", frame);
        button(widgets, "capture frames", video);
        
        begin_line(widgets);
        button(widgets, "[t] freeze time", freeze);
        button(widgets, "[f] reset camera", reset_camera);
        button(widgets, "[c] copy/save camera", copy_camera);
        button(widgets, "[v] paste/read camera", paste_camera);
        
        begin_line(widgets);
        begin_line(widgets);
        label(widgets, "program '%s' running...", program_filename);
        if(mesh_filename && mesh_filename[0])
        {
            begin_line(widgets);
            label(widgets, "mesh '%s', %d vertices %s %s", mesh_filename, mesh.vertex_count(),
                mesh.texcoord_buffer_size() ? "texcoords" : "", mesh.normal_buffer_size() ? "normals" : "");
        }
        for(unsigned int i= 0; i < (unsigned int) texture_filenames.size(); i++)
        {
            begin_line(widgets);
            label(widgets, "texture%u '%s'", i, texture_filenames[i]);
        }
    }
    end(widgets);
    
    draw(widgets, window_width(), window_height());
    
    if(frame || key_state('s'))
    {
        frame= 0;
        clear_key_state('s');
        
        static int calls= 1;
        printf("screenshot %d...\n", calls);
        screenshot("shader_kit", calls++);
    }
    
    if(video) 
        capture("shader_kit");
    
    if(copy_camera || key_state('c'))
    {
        copy_camera= 0;
        clear_key_state('c');
        camera.write_orbiter("orbiter.txt");
    }
    if(paste_camera || key_state('v'))
    {
        paste_camera= 0;
        clear_key_state('v');
        if(camera.read_orbiter("orbiter.txt") < 0)
        {
            camera= Orbiter();
            camera.lookat(mesh_pmin, mesh_pmax);
        }
    }
    
    if(reset_camera || key_state('f'))
    {
        reset_camera= 0;
        clear_key_state('f');
        
        camera= Orbiter();
        camera.lookat(mesh_pmin, mesh_pmax);
    }
    
    return 1;
}
 
 
int main( int argc, char **argv )
{
    if(argc == 1)
    {
        printf("usage: %s shader.glsl [mesh.obj] [texture0.png [texture1.png]]\n", argv[0]);
        return 0;
    }
    
    Window window= create_window(1024, 640);
    if(window == nullptr) 
        return 1;
    
    Context context= create_context(window);
    if(context == nullptr) 
        return 1;
    
    // creation des objets opengl
    std::vector<const char *> options(argv + 1, argv + argc);
    if(init(options) < 0)
    {
        printf("[error] init failed.\n");
        return 1;
    }
    
    // affichage de l'application
    run(window, draw);
 
    // nettoyage
    quit();
    release_context(context);
    release_window(window);
    return 0;
}