Exemple #1
0
int32_t main(int32_t argc, char *argv[]) {
    if( init_sdl2() ) {
        return 1;
    }

    int width = 1280;
    int height = 720;

    SDL_Window* window;
    sdl2_window("cute3d: " __FILE__, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, width, height, &window);

    SDL_GLContext* context;
    sdl2_glcontext(3, 2, window, &context);

    if( init_shader() ) {
        return 1;
    }

    if( init_canvas(width, height) ) {
        return 1;
    }
    canvas_create("global_dynamic_canvas", &global_dynamic_canvas);
    canvas_create("global_static_canvas", &global_static_canvas);

    struct Vbo vbo = {0};
    vbo_create(&vbo);
    vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX, 3, GL_FLOAT, GL_STATIC_DRAW);
    vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX_NORMAL, 3, GL_FLOAT, GL_STATIC_DRAW);
    vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX_COLOR, 4, GL_UNSIGNED_BYTE, GL_STATIC_DRAW);
    vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX_NORMAL, NORMAL_SIZE, GL_FLOAT, GL_STATIC_DRAW);

    struct Ibo ibo = {0};
    ibo_create(GL_TRIANGLES, GL_UNSIGNED_INT, GL_STATIC_DRAW, &ibo);

    struct SolidTetrahedron hard_tetrahedron = {0};
    struct SolidBox hard_cube = {0};
    struct SolidSphere16 hard_sphere16 = {0};
    struct SolidSphere32 hard_sphere32 = {0};
    solid_tetrahedron_create(1.0, (Color){255, 0, 0, 255}, &hard_tetrahedron);
    solid_cube_create(0.5, (Color){0, 255, 0, 255}, &hard_cube);
    solid_sphere16_create(16, 8, 0.75, (Color){0, 255, 255, 255}, &hard_sphere16);
    solid_sphere32_create(32, 16, 0.75, (Color){255, 255, 0, 255}, &hard_sphere32);

    solid_optimize((struct Solid*)&hard_tetrahedron);
    solid_optimize((struct Solid*)&hard_cube);
    solid_optimize((struct Solid*)&hard_sphere16);
    solid_optimize((struct Solid*)&hard_sphere32);

    struct VboMesh hard_tetrahedron_mesh, hard_box_mesh, hard_cube_mesh, hard_sphere16_mesh, hard_sphere32_mesh;
    vbo_mesh_create_from_solid((struct Solid*)&hard_tetrahedron, &vbo, &ibo, &hard_tetrahedron_mesh);
    vbo_mesh_create_from_solid((struct Solid*)&hard_cube, &vbo, &ibo, &hard_cube_mesh);
    vbo_mesh_create_from_solid((struct Solid*)&hard_sphere16, &vbo, &ibo, &hard_sphere16_mesh);
    vbo_mesh_create_from_solid((struct Solid*)&hard_sphere32, &vbo, &ibo, &hard_sphere32_mesh);

    struct SolidTetrahedron smooth_tetrahedron = {0};
    struct SolidBox smooth_cube = {0};
    struct SolidSphere16 smooth_sphere16 = {0};
    struct SolidSphere32 smooth_sphere32 = {0};
    solid_tetrahedron_create(1.0, (Color){255, 0, 0, 255}, &smooth_tetrahedron);
    solid_cube_create(0.5, (Color){0, 255, 0, 255}, &smooth_cube);
    solid_sphere16_create(16, 8, 0.75, (Color){0, 255, 255, 255}, &smooth_sphere16);
    solid_sphere32_create(32, 16, 0.75, (Color){255, 255, 0, 255}, &smooth_sphere32);

    solid_optimize((struct Solid*)&smooth_tetrahedron);
    solid_optimize((struct Solid*)&smooth_cube);
    solid_optimize((struct Solid*)&smooth_sphere16);
    solid_optimize((struct Solid*)&smooth_sphere32);
    solid_smooth_normals((struct Solid*)&smooth_tetrahedron, smooth_tetrahedron.normals, smooth_tetrahedron.normals);
    solid_smooth_normals((struct Solid*)&smooth_cube, smooth_cube.normals, smooth_cube.normals);
    solid_smooth_normals((struct Solid*)&smooth_sphere16, smooth_sphere16.normals, smooth_sphere16.normals);
    solid_smooth_normals((struct Solid*)&smooth_sphere32, smooth_sphere32.normals, smooth_sphere32.normals);

    struct VboMesh smooth_tetrahedron_mesh, smooth_box_mesh, smooth_cube_mesh, smooth_sphere16_mesh, smooth_sphere32_mesh;
    vbo_mesh_create_from_solid((struct Solid*)&smooth_tetrahedron, &vbo, &ibo, &smooth_tetrahedron_mesh);
    vbo_mesh_create_from_solid((struct Solid*)&smooth_cube, &vbo, &ibo, &smooth_cube_mesh);
    vbo_mesh_create_from_solid((struct Solid*)&smooth_sphere16, &vbo, &ibo, &smooth_sphere16_mesh);
    vbo_mesh_create_from_solid((struct Solid*)&smooth_sphere32, &vbo, &ibo, &smooth_sphere32_mesh);

    struct Arcball arcball = {0};
    arcball_create(width, height, (Vec4f){2.5,17.0,17.0,1.0}, (Vec4f){2.5,0.0,0.0,1.0}, 0.1, 100.0, &arcball);

    float circular_motion_angle = 0.0f;
    float circular_motion_speed = (2.0f*PI)/30;
    float circular_motion_radius = 12.0f;

    Vec3f light_position = { circular_motion_radius, 10.0, circular_motion_radius };
    Vec3f light_direction = {0};
    vec_sub((Vec3f){0.0f, 0.0f, 0.0f}, light_position, light_direction);
    vec_normalize(light_direction, light_direction);

    Vec3f eye_position = {0};
    vec_copy3f(arcball.camera.pivot.position, eye_position);

    Color ambiance = {50, 25, 150, 255};
    Color specular = {255, 255, 255, 255};
    float material_shininess = 1.0;
    Vec4f material_coefficients = { 0.8, 0.2, 0.0, 0.0 };

    // flat
    struct Shader flat_shader = {0};
    shader_create(&flat_shader);
    shader_attach(&flat_shader, GL_VERTEX_SHADER, "prefix.vert", 1, "flat_shading.vert");
    shader_attach(&flat_shader, GL_FRAGMENT_SHADER, "prefix.frag", 1, "flat_shading.frag");
    shader_make_program(&flat_shader, SHADER_DEFAULT_NAMES, "flat_shader");

    shader_set_uniform_3f(&flat_shader, flat_shader.program, SHADER_UNIFORM_LIGHT_DIRECTION, 3, GL_FLOAT, light_direction);
    shader_set_uniform_4f(&flat_shader, flat_shader.program, SHADER_UNIFORM_AMBIENT_LIGHT, 4, GL_UNSIGNED_BYTE, ambiance);

    // gouraud
    struct Shader gouraud_shader = {0};
    shader_create(&gouraud_shader);
    shader_attach(&gouraud_shader, GL_VERTEX_SHADER, "prefix.vert", 1, "gouraud_shading.vert");
    shader_attach(&gouraud_shader, GL_FRAGMENT_SHADER, "prefix.frag", 1, "gouraud_shading.frag");
    shader_make_program(&gouraud_shader, SHADER_DEFAULT_NAMES, "gouraud_shader");

    shader_set_uniform_3f(&gouraud_shader, gouraud_shader.program, SHADER_UNIFORM_LIGHT_POSITION, 3, GL_FLOAT, light_position);
    shader_set_uniform_3f(&gouraud_shader, gouraud_shader.program, SHADER_UNIFORM_EYE_POSITION, 3, GL_FLOAT, eye_position);
    shader_set_uniform_4f(&gouraud_shader, gouraud_shader.program, SHADER_UNIFORM_AMBIENT_LIGHT, 4, GL_UNSIGNED_BYTE, ambiance);
    shader_set_uniform_4f(&gouraud_shader, gouraud_shader.program, SHADER_UNIFORM_SPECULAR_LIGHT, 4, GL_UNSIGNED_BYTE, specular);
    shader_set_uniform_1f(&gouraud_shader, gouraud_shader.program, SHADER_UNIFORM_MATERIAL_SHININESS, 1, GL_FLOAT, &material_shininess);
    shader_set_uniform_4f(&gouraud_shader, gouraud_shader.program, SHADER_UNIFORM_MATERIAL_COEFFICIENTS, 4, GL_FLOAT, material_coefficients);
    shader_set_uniform_3f(&gouraud_shader, gouraud_shader.program, SHADER_UNIFORM_EYE_POSITION, 3, GL_FLOAT, &arcball.camera.pivot.position);

    Mat identity = IDENTITY_MAT;
    draw_grid(&global_static_canvas, 0, identity, (Color){127, 127, 127, 255}, 0.03f, 12.0f, 12.0f, 12);

    Mat shading_label_transform = IDENTITY_MAT;
    Quat text_rotation = IDENTITY_QUAT;
    quat_from_axis_angle((Vec3f)X_AXIS, -PI/2.0f, text_rotation);
    mat_rotate(shading_label_transform, text_rotation, shading_label_transform);
    mat_translate(shading_label_transform, (float[4]){ 6.5, 0.0, -2.5, 1.0 }, shading_label_transform);
Exemple #2
0
int32_t main(int32_t argc, char *argv[]) {
    if( init_sdl2() ) {
        return 1;
    }

    SDL_Window* window;
    sdl2_window("test-shading", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1280, 720, &window);

    SDL_GLContext* context;
    sdl2_glcontext(3, 2, window, (Color){0, 0, 0, 255}, &context);

    if( init_shader() ) {
        return 1;
    }

    if( init_vbo() ) {
        return 1;
    }

    if( init_canvas(1280,720) ) {
        return 1;
    }
    canvas_create("global_dynamic_canvas", 1280, 720, &global_dynamic_canvas);
    canvas_create("global_static_canvas", 1280, 720, &global_static_canvas);

    struct Vbo test_vbo = {0};
    vbo_create(&test_vbo);
    vbo_add_buffer(&test_vbo, SHADER_ATTRIBUTE_VERTEX, 3, GL_FLOAT, GL_STATIC_DRAW);

    struct Ibo test_ibo = {0};
    ibo_create(GL_TRIANGLES, GL_UNSIGNED_INT, GL_STATIC_DRAW, &test_ibo);

    struct VboMesh test_mesh1 = {0};
    vbo_mesh_create(&test_vbo, &test_ibo, &test_mesh1);
    float triangle1[3*3] = {1.0, 1.0, 1.0, 2.0, 2.0, 2.0, 3.0, 3.0, 3.0};
    vbo_mesh_append_attributes(&test_mesh1, SHADER_ATTRIBUTE_VERTEX, 3, GL_FLOAT, 3, &triangle1);
    vbo_mesh_print(&test_mesh1);

    struct VboMesh test_mesh2 = {0};
    vbo_mesh_create(&test_vbo, &test_ibo, &test_mesh2);
    float triangle2[3*3] = {4.0, 4.0, 4.0, 5.0, 5.0, 5.0, 6.0, 6.0, 6.0};
    vbo_mesh_append_attributes(&test_mesh2, SHADER_ATTRIBUTE_VERTEX, 3, GL_FLOAT, 3, &triangle2);
    vbo_mesh_print(&test_mesh2);

    struct Vbo vbo = {0};
    vbo_create(&vbo);
    vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX, 3, GL_FLOAT, GL_STATIC_DRAW);
    vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX_NORMAL, 3, GL_FLOAT, GL_STATIC_DRAW);
    vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX_COLOR, 4, GL_UNSIGNED_BYTE, GL_STATIC_DRAW);
    vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_SMOOTH_NORMAL, NORMAL_SIZE, GL_FLOAT, GL_STATIC_DRAW);

    struct Ibo ibo = {0};
    ibo_create(GL_TRIANGLES, GL_UNSIGNED_INT, GL_STATIC_DRAW, &ibo);

    struct SolidTetrahedron tetrahedron = {0};
    solid_tetrahedron_create(1.0, (Color){255, 0, 0, 255}, &tetrahedron);
    solid_optimize((struct Solid*)&tetrahedron);

    struct SolidTetrahedron tetrahedron2 = {0};
    solid_tetrahedron_create(1.0, (Color){255, 0, 255, 255}, &tetrahedron2);
    solid_optimize((struct Solid*)&tetrahedron2);

    struct SolidBox cube = {0};
    solid_cube_create(1.0, (Color){0, 255, 0, 255}, &cube);
    solid_optimize((struct Solid*)&cube);

    struct SolidBox cube2 = {0};
    solid_cube_create(1.0, (Color){0, 255, 255, 255}, &cube2);
    solid_optimize((struct Solid*)&cube2);

    struct VboMesh tetrahedron_mesh;
    vbo_mesh_create_from_solid((struct Solid*)&tetrahedron, &vbo, &ibo, &tetrahedron_mesh);

    struct VboMesh cube_mesh = {0};
    vbo_mesh_create_from_solid((struct Solid*)&cube, &vbo, &ibo, &cube_mesh);

    struct VboMesh tetrahedron_mesh2;
    vbo_mesh_create_from_solid((struct Solid*)&tetrahedron2, &vbo, &ibo, &tetrahedron_mesh2);

    struct VboMesh cube_mesh2 = {0};
    vbo_mesh_create_from_solid((struct Solid*)&cube2, &vbo, &ibo, &cube_mesh2);

    vbo_mesh_print(&tetrahedron_mesh);
    vbo_mesh_print(&tetrahedron_mesh2);

    vbo_mesh_print(&cube_mesh);
    vbo_mesh_print(&cube_mesh2);

    struct Shader flat_shader = {0};
    shader_create(&flat_shader);
    shader_attach(&flat_shader, GL_VERTEX_SHADER, "prefix.vert", 1, "flat_shading.vert");
    shader_attach(&flat_shader, GL_FRAGMENT_SHADER, "prefix.frag", 1, "flat_shading.frag");
    shader_make_program(&flat_shader, "flat_shader");

    Vec4f light_direction = { 0.2, -0.5, -1.0 };
    shader_set_uniform_3f(&flat_shader, flat_shader.program, SHADER_UNIFORM_LIGHT_DIRECTION, 3, GL_FLOAT, light_direction);

    Color ambiance = {50, 25, 150, 255
    };
    shader_set_uniform_4f(&flat_shader, flat_shader.program, SHADER_UNIFORM_AMBIENT_LIGHT, 4, GL_UNSIGNED_BYTE, ambiance);

    struct Arcball arcball = {0};
    arcball_create(window, (Vec4f){0.0,8.0,8.0,1.0}, (Vec4f){0.0,0.0,0.0,1.0}, 0.1, 100.0, &arcball);

    Mat identity;
    mat_identity(identity);

    Quat grid_rotation = {0};
    quat_from_vec_pair((Vec4f){0.0, 0.0, 1.0, 1.0}, (Vec4f){0.0, 1.0, 0.0, 1.0}, grid_rotation);
    Mat grid_transform = {0};
    quat_to_mat(grid_rotation, grid_transform);
    draw_grid(&global_static_canvas, 0, grid_transform, (Color){127, 127, 127, 255}, 0.03f, 12.0f, 12.0f, 12);

    while (true) {
        SDL_Event event;
        while( SDL_PollEvent(&event) ) {
            switch (event.type) {
                case SDL_QUIT:
                    goto done;
                case SDL_KEYDOWN: {
                    SDL_KeyboardEvent* key_event = (SDL_KeyboardEvent*)&event;
                    if(key_event->keysym.scancode == SDL_SCANCODE_ESCAPE) {
                        goto done;
                    }
                    break;
                }
            }

            arcball_event(&arcball, event);
        }

        sdl2_gl_set_swap_interval(1);

        ogl_debug( glClearDepth(1.0f);
                   glClearColor(.0f, .0f, .0f, 1.0f);
                   glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ); );

        Mat transform = {0};
        mat_translate(identity, (float[4]){ -1.0, 1.0, -1.0, 1.0 }, transform);
Exemple #3
0
int32_t main(int32_t argc, char *argv[]) {
    if( init_sdl2() ) {
        return 1;
    }

    SDL_Window* window;
    sdl2_window("test-grid", 100, 60, 1280, 720, &window);

    SDL_GLContext* context;
    sdl2_glcontext(3, 2, window, &context);

    if( init_vbo() ) {
        return 1;
    }

    printf("vbo\n");
    struct Vbo vbo = {0};
    vbo_create(&vbo);
    vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX, 3, GL_FLOAT, GL_STATIC_DRAW);
    vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX_NORMAL, 3, GL_FLOAT, GL_STATIC_DRAW);

    struct Ibo ibo = {0};
    ibo_create(GL_TRIANGLES, GL_UNSIGNED_INT, GL_STATIC_DRAW, &ibo);

    struct Grid grid = {0};
    grid_create(4,4,1,&grid);

    struct GridPages pages = {0};
    grid_pages(&grid,2,2,1,&pages);

    grid_dump(grid,pages);

    struct GridIndex index = {0};
    for( uint64_t z = 0; z < grid.size.z; z++ ) {
        for( uint64_t y = 0; y < grid.size.y; y++ ) {
            for( uint64_t x = 0; x < grid.size.x; x++ ) {
                grid_index_xyz(&grid, &pages, NULL, x, y, z, &index);
                printf("x:%lu y:%lu z:%lu page:%lu cell:%lu\n", x, y, z, index.page, index.cell);
            }
        }
    }

    printf("-----------\n");

    struct GridBox box = {0};
    box.position.x = 1;
    box.position.y = 1;
    box.position.z = 0;
    box.size.x = 2;
    box.size.y = 2;
    box.size.z = 1;
    box.level = 0;

    for( uint64_t z = 0; z < box.size.z; z++ ) {
        for( uint64_t y = 0; y < box.size.y; y++ ) {
            for( uint64_t x = 0; x < box.size.x; x++ ) {
                grid_index_xyz(&grid, &pages, &box, x, y, z, &index);
                printf("x:%lu y:%lu z:%lu page:%lu cell:%lu\n", x, y, z, index.page, index.cell);
            }
        }
    }

    struct GridSize size = {0};
    uint64_t array_size = grid_levelsize(&grid, &pages, 0, &size)->array;
    for( int32_t i = 0; i < array_size; i++ ) {
        grid_index(&grid, &pages, NULL, i, &index);
    }

    uint64_t x = UINT64_MAX;
    printf("0x%lx\n", x);

    grid_alloc(&pages, 0, 0);
    grid_alloc(&pages, 1, 0);
    grid_alloc(&pages, 2, 0);
    grid_alloc(&pages, 3, 0);

    grid_set1(&grid, &pages, NULL, 23);
    grid_set1(&grid, &pages, &box, 42);

    printf("lala\n");

    grid_pagebox(&grid, &pages, 3, 0, &box);
    printf("%lu %lu %lu %lu %lu %lu %d\n", box.position.x, box.position.y, box.position.z, box.size.x, box.size.y, box.size.z, box.level);

    /* grid_pageout(&grid, &pages, 0, NULL); */
    /* printf("\n"); */
    /* grid_pageout(&grid, &pages, 1, NULL); */
    /* printf("\n"); */
    /* grid_pageout(&grid, &pages, 2, NULL); */
    /* printf("\n"); */
    /* grid_pageout(&grid, &pages, 3, NULL); */
    /* printf("\n"); */

    return 0;
}
Exemple #4
0
int32_t main(int32_t argc, char *argv[]) {
    printf("<<watchlist//>>\n");

    if( init_sdl2() ) {
        return 1;
    }

    int32_t width = 1280;
    int32_t height = 720;

    SDL_Window* window;
    sdl2_window("cute3d: " __FILE__, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, width, height, &window);

    SDL_GLContext* context;
    sdl2_glcontext(3, 2, window, &context);

    if( init_shader() ) {
        return 1;
    }

    if( init_vbo() ) {
        return 1;
    }

    if( init_canvas(1280,720) ) {
        return 1;
    }
    canvas_create("global_dynamic_canvas", &global_dynamic_canvas);
    canvas_create("global_static_canvas", &global_static_canvas);

    struct Vbo vbo = {0};
    vbo_create(&vbo);
    vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX, 3, GL_FLOAT, GL_STATIC_DRAW);
    vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX_NORMAL, 3, GL_FLOAT, GL_STATIC_DRAW);
    vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX_COLOR, 4, GL_UNSIGNED_BYTE, GL_STATIC_DRAW);

    struct Ibo ibo = {0};
    ibo_create(GL_TRIANGLES, GL_UNSIGNED_INT, GL_STATIC_DRAW, &ibo);

    struct CollisionEntity entity_a = {0};
    entity_create("red", (Color){ 255, 0, 0, 255 }, &vbo, &ibo, &entity_a);
    /* quat_mul_axis_angle(entity_a.pivot.orientation, (Vec4f)UP_AXIS, PI/4, entity_a.pivot.orientation); */
    /* quat_mul_axis_angle(entity_a.pivot.orientation, (Vec4f)RIGHT_AXIS, PI/2 + 0.2, entity_a.pivot.orientation); */
    vec_add(entity_a.pivot.position, (Vec4f){0.2, 0.15, 0.8, 1.0}, entity_a.pivot.position);

    struct CollisionEntity entity_b = {0};
    entity_create("green", (Color){ 0, 255, 0, 255 }, &vbo, &ibo, &entity_b);
    quat_mul_axis_angle(entity_b.pivot.orientation, (Vec4f)RIGHT_AXIS, PI/4 - 0.2, entity_b.pivot.orientation);
    quat_mul_axis_angle(entity_b.pivot.orientation, (Vec4f)UP_AXIS, PI/2 + 0.0, entity_b.pivot.orientation);

    struct Shader flat_shader = {0};
    shader_create(&flat_shader);
    shader_attach(&flat_shader, GL_VERTEX_SHADER, "prefix.vert", 1, "flat_shading.vert");
    shader_attach(&flat_shader, GL_FRAGMENT_SHADER, "prefix.frag", 1, "flat_shading.frag");
    shader_make_program(&flat_shader, SHADER_DEFAULT_NAMES, "flat_shader");

    Vec4f light_direction = { 0.2, -0.5, -1.0 };
    shader_set_uniform_3f(&flat_shader, flat_shader.program, SHADER_UNIFORM_LIGHT_DIRECTION, 3, GL_FLOAT, light_direction);

    Color ambiance = { 65, 25, 50, 255 };
    shader_set_uniform_4f(&flat_shader, flat_shader.program, SHADER_UNIFORM_AMBIENT_LIGHT, 4, GL_UNSIGNED_BYTE, ambiance);

    struct Arcball arcball = {0};
    arcball_create(width, height, (Vec4f){5.0, 3.0, 5.0, 1.0}, (Vec4f){0.0, 0.0, 0.0, 1.0}, 1.0, 1000.0, &arcball);

    size_t num_entities = 2;
    struct PickingSphere* picking_spheres[2];
    picking_spheres[0] = &entity_a.picking_sphere;
    picking_spheres[1] = &entity_b.picking_sphere;

    struct CollisionEntity* picking_entities[2];
    picking_entities[0] = &entity_a;
    picking_entities[1] = &entity_b;

    struct GameTime time = {0};
    gametime_create(1.0f / 60.0f, &time);

    draw_grid(&global_static_canvas, 0, (Mat)IDENTITY_MAT, (Color){127, 127, 127, 127}, 0.01f, 12.0f, 12.0f, 12);

    while (true) {

        SDL_Event event;
        while( sdl2_poll_event(&event) ) {
            if( sdl2_handle_quit(event) ) {
                goto done;
            }
            sdl2_handle_resize(event);

            if( picking_sphere_drag_event(&arcball.camera, num_entities, picking_spheres, event) ) {
                struct CollisionEntity* selected_entity = NULL;
                float nearest = -FLT_MIN;
                for( size_t i = 0; i < num_entities; i++ ) {
                    if( picking_spheres[i]->picked && ( picking_spheres[i]->front < nearest || nearest < 0.0f ) ) {
                        nearest = picking_spheres[i]->front;
                        selected_entity = picking_entities[i];
                    }
                }

                static int32_t last_x = -1;
                static int32_t last_y = -1;
                if( selected_entity != NULL ) {
                    if( last_x > -1 && last_y > -1 ) {
                        float distance = selected_entity->picking_sphere.front;

                        Vec4f a = {0};
                        camera_ray(&arcball.camera, CAMERA_PERSPECTIVE, last_x, last_y, a);
                        vec_mul1f(a, distance, a);

                        Vec4f b = {0};
                        camera_ray(&arcball.camera, CAMERA_PERSPECTIVE, event.motion.x, event.motion.y, b);
                        vec_mul1f(b, distance, b);

                        Vec4f move = {0};
                        vec_sub(b, a, move);
                        float length = vec_length(move);

                        move[1] = 0.0f;
                        vec_normalize(move, move);
                        vec_mul1f(move, length, move);

                        vec_add(selected_entity->pivot.position, move, selected_entity->pivot.position);
                    }

                    last_x = event.motion.x;
                    last_y = event.motion.y;
                }

                if( event.type == SDL_MOUSEBUTTONUP ) {
                    last_x = -1;
                    last_y = -1;
                }
            } else {
                arcball_handle_resize(&arcball, event);
                arcball_handle_mouse(&arcball, event);
            }
        }

        sdl2_gl_set_swap_interval(0);

        gametime_advance(&time, sdl2_time_delta());

        ogl_debug( glClearDepth(1.0f);
                   glClearColor(.0f, .0f, .0f, 1.0f);
                   glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ); );

        Mat projection_mat = {0};
        Mat view_mat = {0};
        camera_matrices(&arcball.camera, CAMERA_PERSPECTIVE, projection_mat, view_mat);

        Mat identity = {0};
        mat_identity(identity);

        Mat transform_a = {0};
        pivot_world_transform(&entity_a.pivot, transform_a);
        //vbo_mesh_render(&entity_a.vbo_mesh, &flat_shader, &arcball.camera, transform_a);
        draw_halfedgemesh_wire(&global_dynamic_canvas, 0, transform_a, (Color){255, 0, 0, 255}, 0.02f, &entity_a.hemesh);

        Mat transform_b = {0};
        pivot_world_transform(&entity_b.pivot, transform_b);
        //vbo_mesh_render(&entity_b.vbo_mesh, &flat_shader, &arcball.camera, transform_b);
        draw_halfedgemesh_wire(&global_dynamic_canvas, 0, transform_b, (Color){0, 255, 0, 255}, 0.02f, &entity_b.hemesh);

        Mat between_transform = {0};
        pivot_between_transform(&entity_a.pivot, &entity_b.pivot, between_transform);

        Vec3f foo = {0};
        mat_mul_vec(between_transform, entity_a.hemesh.vertices.array[0].position, foo);

        struct CollisionConvexConvex collision = {0};
        struct CollisionParameter collision_parameter = {
            .face_tolerance = 0.9,
            .edge_tolerance = 0.95,
            .absolute_tolerance = 0.025
        };
        collision_create_convex_convex(&entity_a.hemesh, &entity_a.pivot,
                                       &entity_b.hemesh, &entity_b.pivot,
                                       collision_parameter,
                                       &collision);

        if( collision_test_convex_convex(&collision) ) {
            collision_contact_convex_convex(&collision);
            //printf("//collision: %d\n", collision_counter);

            const struct Contacts* contacts = &collision.contacts;
            VecP* m = contacts->points[contacts->num_contacts-1];
            for( int32_t i = 0; i < contacts->num_contacts; i++ ) {
                VecP* n = contacts->points[i];
                draw_line(&global_dynamic_canvas, 0, transform_b, (Color){255, 255, 255, 255}, 0.08f, m, n);
                m = n;
            }
        }

        gametime_integrate(&time);
        Vec4f screen_cursor = {0,0,0,1};
        text_show_fps(&global_dynamic_canvas, 0, screen_cursor, 0, 0, (Color){255, 255, 255, 255}, 20.0, "default_font", time.frame);

        canvas_render_layers(&global_static_canvas, 0, 0, &arcball.camera, (Mat)IDENTITY_MAT);

        canvas_render_layers(&global_dynamic_canvas, 0, 0, &arcball.camera, (Mat)IDENTITY_MAT);
        canvas_clear(&global_dynamic_canvas);

        sdl2_gl_swap_window(window);
    }


done:
    SDL_Quit();
    printf("done\n");
    return 0;
}