Subversion Repositories gelsvn

// ----------------------------------------

// A simple OBJ viewer.

//

// Controls:

// - left mouse down + mouse motion : rotate

// - Scroll button and +- buttons   : zoom

// - right mouse click              : centre trackball

// - esc                            : exits

// - x,y,z buttons                  : switch trackball up axis

// - w                              : toggle wireframe on/off

// - t                              : toggle texture on/off

// - f                              : switch between vertex and face normals

// ----------------------------------------

#include <fstream>

#include <iostream>

#include <string>

#include <GL/glew.h>

#include "Util/ArgExtracter.h"

#include "CGLA/Vec2i.h"

#include "CGLA/Vec3f.h"

#include "GLGraphics/gel_glut.h"

#include "GLGraphics/QuatTrackBall.h"

#include "GLGraphics/draw.h"

#include "Geometry/TriMesh.h"

#include "Geometry/load.h"

#include "Geometry/GridAlgorithm.h"

#include "Geometry/HGrid.h"

using namespace std;

using namespace CGLA;

using namespace Geometry;

using namespace GLGraphics;

int win_size_x = 800;

int win_size_y = 800;

bool per_vertex_normals = 1;

bool redo_display_list = 1;

bool do_wireframe = false;

Vec3f line_col = Vec3f(1,0,0);

QuatTrackBall* ball;

int spin_timer = 20;

void spin(int x);

int main_window;

TriMesh mesh;

bool do_textures = true;

bool depth_pick(int x, int y,Vec3f& wp)

{

	// Enquire about the viewport dimensions

	GLint viewport[4];

	glGetIntegerv(GL_VIEWPORT, viewport);

	// Get the minimum and maximum depth values.

	float minmax_depth[2];

	glGetFloatv(GL_DEPTH_RANGE, minmax_depth);

	// Read a single pixel at the position of the mouse cursor.

	float depth;

	glReadPixels(x, viewport[3]-y, 1,1, GL_DEPTH_COMPONENT,

				 GL_FLOAT, (void*) &depth);

	// If the depth corresponds to the far plane, we clicked on the

	// background.

	if(depth == minmax_depth[1])

		return false;

	// The lines below copy the viewing transformation from OpenGL

	// to local variables. The call to gluLookAt must have exactly

	// the same parameters as when the scene is drawn.

	glLoadIdentity();

	ball->set_gl_modelview();

	double mvmat[16];

	glGetDoublev(GL_MODELVIEW_MATRIX, mvmat);

	// Copy the projection matrix. We assume it is unchanged.

	double prjmat[16];

	glGetDoublev(GL_PROJECTION_MATRIX, prjmat);

	// Now unproject the point from screen to world coordinates.

	double ox, oy, oz;

	gluUnProject(x,viewport[3]-y,depth,

				 mvmat,prjmat,viewport,

				 &ox, &oy, &oz);

	wp = Vec3f(ox,oy,oz);

	return true;

}

void mouse_motion(int x, int y)

{

    ball->roll_ball(Vec2i(x,y));

}

void mouse(int btn, int state, int x, int y)

{

	if(state == GLUT_DOWN) 

	{

		if(btn == GLUT_LEFT_BUTTON) 

			ball->grab_ball(ROTATE_ACTION, Vec2i(x,y));

		else if(btn == GLUT_MIDDLE_BUTTON) 

			ball->grab_ball(ZOOM_ACTION, Vec2i(x, y));

		else if(btn == GLUT_RIGHT_BUTTON) 

			ball->grab_ball(PAN_ACTION, Vec2i(x, y));

	}

	else if(state == GLUT_UP)

		ball->release_ball();	

}

void spin(int x)

{

	ball->do_spin();

	glutTimerFunc(spin_timer, spin, 0);  

	glutPostRedisplay();

}

void setupshader()

{

	static GLuint vs,fs,prog;

	static bool was_here = false;

	if(!was_here)

	{

		was_here = true;

		const string vss = 

		"varying vec3 n;\n"

		"varying vec3 v;\n"

		"varying vec3 v_obj;\n"

		"\n"

		"void main(void)\n"

		"{\n"

		"	gl_Position = ftransform();\n"

		"   v_obj = gl_Vertex.xyz;\n"

		"	v = vec3(gl_ModelViewMatrix * gl_Vertex);\n"

		"	n = normalize(gl_NormalMatrix * gl_Normal);\n"

		"}\n"

		"\n";

		const string fss =

		"varying vec3 n;\n"

		"varying vec3 v;\n"

		"varying vec3 v_obj;\n"

		"\n"

		"vec4 glazed_shader(vec4 mat_col,  vec4 light_col, vec3 light_dir)\n"

		"{\n"

		"	vec3 e = normalize(-v);\n"

		"	vec3 r = normalize(2.0*dot(e, n)*n - e);\n"

		"	float d = max(0.05,dot(light_dir, n));\n"

		"	vec4 diff = mat_col * light_col *d; 	\n"

		"	vec4 refl = smoothstep(0.7,0.75,dot(r,light_dir)) * light_col;\n"

		"	return 0.1*refl + 2.25*diff;\n"

		"}\n"

		"\n"

		"void main(void)\n"

		"{\n"

		"	vec4 mat_col = vec4(0.7,0.6,1.0,1.0);\n"

		"	\n"

		"	vec3 light0_dir = vec3(0.0,1.0,0.0);\n"

		"	vec4 light0_col = vec4(0.9,0.95,0.95,1.0);\n"

		"	\n"

		"	vec3 light1_dir = vec3(0.0,0.0,1.0);\n"

		"	vec4 light1_col = vec4(.8,.8,.6,1.0);\n"

		"	\n"

		"	gl_FragColor = \n"

		"	0.5*glazed_shader(mat_col, light0_col, light0_dir)+\n"

		"	0.5*glazed_shader(mat_col, light1_col, light1_dir);\n"

		"	\n"

		"	gl_FragColor.a = 1.0;\n"

		"}\n";

		vs = create_glsl_shader(GL_VERTEX_SHADER, vss);

		print_glsl_program_log(vs);

		fs = create_glsl_shader(GL_FRAGMENT_SHADER, fss);

		print_glsl_program_log(fs);

		prog = glCreateProgram();

		if(vs) glAttachShader(prog, vs);

		if(fs) glAttachShader(prog, fs);

		glLinkProgram(prog);

		print_glsl_program_log(prog);

	}

	glUseProgram(prog);

}

void display()

{

	static unsigned int l;

    if(redo_display_list)

    {

        cout << "Creating display list" << endl;

        l = glGenLists(1);

        glNewList(l, GL_COMPILE);

        draw(mesh, per_vertex_normals);

        glEndList();

        redo_display_list = false;

		glutTimerFunc(spin_timer, spin, 0);	

	}

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glLoadIdentity();

    ball->set_gl_modelview();

	if(do_wireframe)

	{

		if(GLEW_EXT_geometry_shader4)

			draw_triangles_in_wireframe(mesh, per_vertex_normals, Vec3f(1,0,0));

		else

			draw_wireframe_oldfashioned(mesh, per_vertex_normals, Vec3f(1,0,0));

	}

	else if(!do_textures)

	{

		setupshader();	

		glCallList(l);

	}

	else

		glCallList(l);

    glutSwapBuffers();

}

void keyboard(unsigned char key, int x, int y)

{

    switch(key)

    {

		case '\033': exit(0); break;

		case 'w': do_wireframe = !do_wireframe; break;

		case 'f': per_vertex_normals = !per_vertex_normals; redo_display_list = true; break;

		case 's': 

		{

			ofstream f("ball.out", ios::binary);

			if(f) f.write(reinterpret_cast<const char*>(ball),sizeof(QuatTrackBall));

		}

		case 'l':

		{

			ifstream f("ball.out", ios::binary);

			if(f) f.read(reinterpret_cast<char*>(ball),sizeof(QuatTrackBall));

		}

		case 't': do_textures = !do_textures;

		break;

    }

	redo_display_list=true;

}

int main(int argc, char** argv)

{

	Util::ArgExtracter ae(argc, argv);

	bool redo_normals = ae.extract("-n");

    // GLUT INIT

    glutInitDisplayMode(GLUT_RGBA|GLUT_DOUBLE|GLUT_DEPTH);

    glutInitWindowSize(win_size_x, win_size_y);

    glutInit(&argc, argv);

    main_window = glutCreateWindow("OBJ Viewer");

    glutDisplayFunc(display);

    glutKeyboardFunc(keyboard);

    glutMotionFunc(mouse_motion);

    glutMouseFunc(mouse);

	glewInit();

    // GL INIT

    glClearColor(.8f, 0.9f, 1.0f, 0.f);

    glEnable(GL_DEPTH_TEST);

    glEnable(GL_LIGHTING);

    glEnable(GL_LIGHT0);

    glLightModeli(GL_LIGHT_MODEL_TWO_SIDE, 1);

    glShadeModel(GL_SMOOTH);

    // LOAD OBJ

    string fn;

    if(ae.no_remaining_args() > 1)

        fn = ae.get_last_arg();

    else

        fn = "../../data/head.obj";

	load(fn, mesh);

	load_textures(mesh);

	if(!mesh.has_normals() || redo_normals)

	{

		cout << "Computing normals" << endl;

		mesh.compute_normals();

	}

	// Initialize Trackball

	Vec3f c;

	float r;

	mesh.get_bsphere(c,r);

	r *= 1.5;

	ball = new QuatTrackBall(c,r,800,800);

	// Setup projection

	glMatrixMode(GL_PROJECTION);

	glLoadIdentity();

	gluPerspective(53,1.0f,r/100.0,r*3.0);

	glMatrixMode(GL_MODELVIEW);

	// Pass control to GLUT

	glutMainLoop();

	return 0;

}