/// LSU EE 7700-1 (Sp 2009), Graphics Processors // /// Homework 4 /// Due: Thursday, 12 March 2009 // E-mail this file (with solution). // Note: Homework 5 will be due the following Monday. /// Name: // $Id:$ <- This is not your student ID, don't change this line! /// Instructions // If necessary, follow the class account setup instructions linked to // the class procedures page, // http://www.ece.lsu.edu/koppel/gp/proc.html // For instructions on how to check out edit, compile, and debug, see // the "Programming Homework Work Flow" entry on the procedures page, // http://www.ece.lsu.edu/koppel/gp/proc.html. // // For those instructions you need to know that: // // This assignment is at SVN URI https://svn.ece.lsu.edu/svn/gp/hw/2009/hw4 // // The assignment instructions are in file hw4.cc. (This file.) // The OpenGL spec, needed for this assignment, is at // http://www.ece.lsu.edu/koppel/gp/refs/glspec21.pdf // The relevant sections are 2.7, 2.8, and 2.9. (Vertex specification, // vertex arrays, and buffer objects.) // For the solutions to the problems below edit this file, even if // it makes more sense to edit others (namely, coord.h). If it seems // that coord.h must be edited, contact me. // The main code is in routine Tube::render(). /// Overview // This file renders the undulating tube using glDrawElements, // with coordinates, normals, and the index (element) array all on // the CPU. In problem 1 move the index array to the gpu, in // problem 2 move coordinates, normals to the gpu as well. /// Keyboard Commands // // 'v' Switch location of vertex data used by glDrawElements. // 0: Index, coordinates, and normals all on CPU. // 1: [When problem 1 solved.] Index on GPU, coord & norm on CPU. // 2: [When problem 2 solved.] Index, coord, & norm on GPU. // // 'p' Pause tube. When paused vertex information is not re-computed // every frame. /// Variables // Selected program variables can be modified using the keyboard. // Use "Tab" to cycle through the variable to be modified, the // name of the variable is displayed next to "VAR" on the bottom // line of green text. // Use '+' (or '=') and '-' (or '_') to change the variable. // (Search for 'variable_control.insert' to find examples of how to // add your own variables.) // // VAR Light Intensity - The light intensity. // VAR Pattern Levels - The number of rings of triangles (along the z axis). // /// Eye and Light Location // Arrows, Page Up, Page Down // Move either the light or the eye. // After pressing 'l' the keys move the light, after pressing 'e' // they move the eye (viewer location). The eye and light location // coordinates are displayed in the upper left. // /// Eye Direction // Home, End, Delete, Insert // Turn the eye direction. // Home should rotate eye direction up, End should rotate eye // down, Delete should rotate eye left, Insert should rotate eye // right. The eye direction vector is displayed in the upper left. /// Problem 0 // Fill in your name in the comment near the top of this file, then // build and run the program. It should display a tube similar to the // one seen in class. Try out the keyboard commands described below // and promptly resolve any problems, feel free to ask for help from // Dr. Koppelman or others, especially on issues of missing libraries, // and other setup problems. // [ ] Name placed at top of this file. // [ ] Code compiles and runs. // [ ] Had fun moving through the tube. /// Problem 1 // Modify the code below so that when opt_v_buffering == 1 // the glDrawElements command uses an element (index) array located on // the gpu. The index array should only be updated when necessary. // [ ] Have glDrawElements use a gpu-located element array. // [ ] Increment num_bytes by the amount of data that should be transferred. /// Problem 2 // Modify the code below so that when opt_v_buffering == 2 // the the index array, normal array, and coordinate array // used by glDrawElements command are all on the gpu. The // respective arrays should be moved to the gpu only when // necessary. (For example, it is not necessary to move data // to the gpu if it already has that data.) Note that the // cpu code reads the same array (vertex_info) twice, once for // coordinates and once for normals. It is okay to do the same // for the gpu-located data. // [ ] Have glDrawElements use gpu-located element, coor, and normal arrays. // [ ] Increment num_bytes by the amount of data that should be transferred. /// Problem 3 // Consider the difference between cpu-located information // (opt_v_buffering == 0) and gpu-located information // (opt_v_buffering==2). When answering the question below look at // performance both in paused and unpaused mode, where performance // includes GPU and CPU time and % utilization. Note that the // transfer rate (MB/s) is something we estimate, while the GPU and // CPU time and % utilization is something that is directly // measured. // Is the change in CPU usage more, less, or equal to what one might // expect given the change in the transfer rate? Explain your // answer. // Is the change in GPU usage more, less, or equal to what one // might expect from the change in transfer rate? Explain. #include <stdio.h> #include <strings.h> #include <stdlib.h> #include <deque> #define GL_GLEXT_PROTOTYPES #define GLX_GLXEXT_PROTOTYPES #include <GL/gl.h> #include <GL/glext.h> #include <GL/glx.h> #include <GL/glxext.h> #include <GL/glu.h> #include <GL/freeglut.h> #include "util.h" #include "coord.h" // Display a tetrahedron, used to indicate light position. // void insert_tetrahedron(pCoor& loc, float size) { pCoor v0(loc.x,loc.y,loc.z); pCoor v1(loc.x,loc.y-size,loc.z+size); pCoor v2(loc.x-.866*size,loc.y-size,loc.z-0.5*size); pCoor v3(loc.x+.866*size,loc.y-size,loc.z-0.5*size); static pColor c1(0xffffff); static pColor c2(0xff00); glDisable(GL_LIGHTING); #define TRI(va,vb,vc) \ { \ pVect n = cross(va,vb,vc); \ glNormal3fv(n); \ glColor3fv(c1); glVertex3fv(va); \ glColor3fv(c2); glVertex3fv(vb); \ glVertex3fv(vc); \ } glBegin(GL_TRIANGLES); TRI(v0,v1,v2); TRI(v0,v2,v3); TRI(v0,v3,v1); glEnd(); # undef TRI glEnable(GL_LIGHTING); } // Class for re-using sine and cosine values. // class MTrig { public: MTrig():size(0),storage(NULL){} void init(int sizep){ size = sizep; if ( storage ) delete storage; storage = new float[size]; idx = 0; full = false; } float sin(float theta){ return trig(theta,::sin); } float cos(float theta){ return trig(theta,::cos); } private: float trig(float theta,double (*func)(double)) { // return func(theta); if ( !full ) { storage[idx] = func(theta); full = idx == size - 1; } if ( idx == size ) idx = 0; return storage[idx++]; } int size; float* storage; int idx; bool full; }; struct Vertex_Info { pCoor pos; pVect nor; }; /// /// Tube Class /// class Tube { public: Tube(pOpenGL_Helper &fb):ogl_helper(fb){ init(); } static void render_w(void *moi){ ((Tube*)moi)->render(); } void init(); void modelview_update(); void render(); private: pOpenGL_Helper &ogl_helper; pVariable_Control variable_control; pFrame_Timer frame_timer; pCoor eye_location; pVect eye_direction; pMatrix modelview; bool opt_move_light; bool opt_pause; float r0; float x_shift; float pattern_pitch_z; float opt_pattern_levels; float opt_pattern_width; float opt_light_intensity; int opt_v_buffering; pCoor opt_light_location; double time_app_start; Vertex_Info *vertex_info; int *index_array; int num_vtx_alloc; int num_indices; MTrig tarray; }; void Tube::init() { time_app_start = time_wall_fp(); // Tell frame timer that work unit is "MB/s" and how should be scaled. // frame_timer.work_unit_set("MB/s",1e-6); r0 = 2; // Tube radius. x_shift = 0.4; // Tube x offset. pattern_pitch_z = 0.25; // Triangle size (z axis). opt_pattern_levels = 100; // Tube depth (z direction.) opt_pattern_width = 80; // Triangle size (circumferential). opt_light_intensity = 2; opt_v_buffering = 0; opt_light_location.set(( r0 - 0.1 ), 0, -3 ); opt_pause = false; eye_location.set(0,0,2.5); eye_direction.set(0,0,-1); modelview_update(); // Arrange that variables below can be modified from the keyboard. // variable_control.insert(opt_light_intensity,"Light Intensity"); variable_control.insert(opt_pattern_levels,"Pattern Levels"); vertex_info = NULL; index_array = 0; num_vtx_alloc = 0; num_indices = 0; } void Tube::modelview_update() { pMatrix_Translate center_eye(-eye_location); pMatrix_Rotation rotate_eye(eye_direction,pVect(0,0,-1)); modelview = rotate_eye * center_eye; } void Tube::render() { frame_timer.frame_start(); glClearColor(0,0,0.0,0.5); glClearDepth(1.0); glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ); // Have frame timer provide timing information for top of image. // ogl_helper.fbprintf("%s\n",frame_timer.frame_rate_text_get()); /// /// Transformation Matrix Setup /// glMatrixMode(GL_MODELVIEW); glLoadTransposeMatrixf(modelview); const int win_width = ogl_helper.get_width(); const int win_height = ogl_helper.get_height(); const float aspect = float(win_width) / win_height; glMatrixMode(GL_PROJECTION); glLoadIdentity(); glFrustum(-0.8,+0.8,-0.8/aspect,0.8/aspect,1,5000); glViewport(0, 0, win_width, win_height); pError_Check(); /// /// Adjust options based on user input. /// pVect adjustment(0,0,0); pVect user_rot_axis(0,0,0); switch ( ogl_helper.keyboard_key ) { case FB_KEY_LEFT: adjustment.x = -0.1; break; case FB_KEY_RIGHT: adjustment.x = 0.1; break; case FB_KEY_UP: adjustment.z = -0.1; break; case FB_KEY_DOWN: adjustment.z = 0.1; break; case FB_KEY_PAGE_DOWN: adjustment.y = -0.1; break; case FB_KEY_PAGE_UP: adjustment.y = 0.1; break; case FB_KEY_DELETE: user_rot_axis.y = 1; break; case FB_KEY_INSERT: user_rot_axis.y = -1; break; case FB_KEY_HOME: user_rot_axis.x = 1; break; case FB_KEY_END: user_rot_axis.x = -1; break; case 'p': case 'P': opt_pause = !opt_pause; break; case 'l': case 'L': opt_move_light = true; break; case 'e': case 'E': opt_move_light = false; break; case 'v': case 'V': opt_v_buffering++; if ( opt_v_buffering == 3 ) opt_v_buffering = 0; break; case 9: variable_control.switch_var_right(); break; case '-':case '_': variable_control.adjust_lower(); break; case '+':case '=': variable_control.adjust_higher(); break; default: break; } // Update eye_direction based on keyboard command. // if ( user_rot_axis.x || user_rot_axis.y ) { pMatrix_Rotation rotall(pVect(0,0,-1),eye_direction); user_rot_axis *= rotall; eye_direction *= pMatrix_Rotation(user_rot_axis, M_PI * 0.03); modelview_update(); } // Update eye_location based on keyboard command. // if ( adjustment.x || adjustment.y || adjustment.z ) { const double angle = fabs(eye_direction.y) > 0.99 ? 0 : atan2(eye_direction.x,-eye_direction.z); pMatrix_Rotation rotall(pVect(0,1,0),-angle); adjustment *= rotall; if ( opt_move_light ) opt_light_location += adjustment; else eye_location += adjustment; modelview_update(); } // // User Messages (Magically inserted into frame buffer.) // ogl_helper.fbprintf ("Eye location: [%.1f, %.1f, %.1f] " "(%suse arrow and page keys to move).\n", eye_location.x, eye_location.y, eye_location.z, opt_move_light ? "press 'e' then " : "" ); ogl_helper.fbprintf ("Light location: [%.1f, %.1f, %.1f] " "(%suse arrow and page keys to move).\n", opt_light_location.x, opt_light_location.y, opt_light_location.z, opt_move_light ? "" : "press 'l' then "); ogl_helper.fbprintf ("Eye direction: [%.2f, %.2f, %.2f] " "(use 'Home', 'End', 'Del', 'Insert' keys to turn).\n", eye_direction.x, eye_direction.y, eye_direction.z); glLightModeli(GL_LIGHT_MODEL_TWO_SIDE,0); glLightfv(GL_LIGHT0, GL_POSITION, opt_light_location); const float light_intensity[4] = {opt_light_intensity, opt_light_intensity, opt_light_intensity, 1.0}; const float light_off[4] = {0,0,0,0}; const float light_dim[4] = {0.1,0.1,0.1,1}; glLightModelfv(GL_LIGHT_MODEL_AMBIENT, &light_dim[0]); glLightfv(GL_LIGHT0, GL_DIFFUSE, &light_intensity[0]); glLightfv(GL_LIGHT0, GL_AMBIENT, &light_off[0]); glLightf(GL_LIGHT0, GL_CONSTANT_ATTENUATION, 0); glLightf(GL_LIGHT0, GL_LINEAR_ATTENUATION, 1); glLightf(GL_LIGHT0, GL_QUADRATIC_ATTENUATION, 0.25); glEnable(GL_LIGHT0); glEnable(GL_LIGHTING); glColorMaterial(GL_FRONT_AND_BACK,GL_AMBIENT_AND_DIFFUSE); glEnable(GL_COLOR_MATERIAL); const char* const v_buffering_str[] = { "Client Data & Indices", "Client Data, GPU Indices", "GPU Data & Indices" }; ogl_helper.fbprintf ("Vertex specification: %s (v to change)\n", v_buffering_str[opt_v_buffering]); if ( opt_pause ) ogl_helper.fbprintf("** PAUSED ** (Press 'p' to unpause.)\n"); else ogl_helper.fbprintf("Press 'p' to pause.\n"); pVariable_Control_Elt* const cvar = variable_control.current; ogl_helper.fbprintf("VAR %s = %.3f\n",cvar->name,cvar->var[0]); glEnable(GL_DEPTH_TEST); glDepthFunc(GL_LESS); // Insert marker (green tetrahedron) to show light location. // insert_tetrahedron(opt_light_location,0.05); // // Insert a tessellated tube in the vertex list. // float z = -1; pColor color_purple(0x580da6); // LSU Spirit Purple pColor color_gold(0xf9b237); // LSU Spirit Gold // // Get Tube Specifications // const float ampl = 0.2; const int pattern_width = 3 * int( opt_pattern_width * 0.33333333 ); const int pattern_levels = int( opt_pattern_levels + 0.5 ); const int num_vtx = pattern_levels * pattern_width; const double cycles_per_second = 0.2; const double phase_n = ( time_wall_fp() - time_app_start ) * cycles_per_second; const double phase = phase_n * 2.0 * M_PI; const float wavelength_z = 4.8; const float radians_per_z = 2.0 * M_PI / wavelength_z; int num_bytes = 0; glEnable(GL_NORMALIZE); glEnable(GL_RESCALE_NORMAL); // If number of vertices has changed re-allocate our storage // (coor_buffer, norm_buffer) and MTrig object and also remember // that gpu's buffer needs to be updated. if ( num_vtx_alloc != num_vtx ) { if ( vertex_info ) { delete vertex_info; delete index_array; index_array = NULL; } vertex_info = new Vertex_Info[num_vtx]; tarray.init( pattern_width * 2 * 2 ); num_vtx_alloc = num_vtx; } // Outer Loop: z axis (down axis of tube). // if ( !opt_pause ) { Vertex_Info *vip = vertex_info; const float ep = 1.00001; const float two_pi = 2 * M_PI; const float delta_theta = ep * two_pi / pattern_width; const float delta_theta_half = 0.5 * delta_theta; for ( int i = 0; i < pattern_levels; i++ ) { const float angle_z = phase + radians_per_z * z; const float cos_z = cos(angle_z); const float theta_0 = i & 1 ? delta_theta_half : 0; const float r = r0 * ( 1 + ampl * sin( angle_z ) ); for ( float theta = theta_0; theta < two_pi; theta += delta_theta ) { const float cos_theta = tarray.cos(theta); const float sin_theta = tarray.sin(theta); Vertex_Info* const vi = vip++; vi->pos = pCoor(x_shift + r * cos_theta, r * sin_theta, z); vi->nor = pVect(-cos_theta,-sin_theta,cos_z); } z -= pattern_pitch_z; } } if ( !index_array ) { index_array = new int[num_vtx*6]; int *iptr = index_array; for ( int i = 0; i < pattern_levels - 1; i++ ) { int vtx_a = pattern_width * ( i & 1 ? i + 1 : i ); int vtx_b = pattern_width * ( i & 1 ? i : i + 1 ); for ( int j = 0; j < pattern_width; j++ ) { const bool last = j == pattern_width - 1; *iptr++ = vtx_a; *iptr++ = vtx_b; vtx_a++; if ( last ) vtx_a -= pattern_width; *iptr++ = vtx_a; *iptr++ = vtx_a; *iptr++ = vtx_b; vtx_b++; if ( last ) vtx_b -= pattern_width; *iptr++ = vtx_b; } } num_indices = iptr - index_array; } pError_Check(); glColor3fv( color_gold ); switch ( opt_v_buffering ) { case 0: glNormalPointer(GL_FLOAT,sizeof(Vertex_Info),&vertex_info[0].nor); glVertexPointer(3,GL_FLOAT,sizeof(Vertex_Info),&vertex_info[0].pos); glEnableClientState(GL_NORMAL_ARRAY); glEnableClientState(GL_VERTEX_ARRAY); glDrawElements(GL_TRIANGLES,num_indices,GL_UNSIGNED_INT,index_array); glDisableClientState(GL_NORMAL_ARRAY); glDisableClientState(GL_VERTEX_ARRAY); pError_Check(); num_bytes += ( sizeof(float) * 6 + sizeof(int) ) * num_indices; break; case 1: // Problem 1 solution here (and other places). break; case 2: // Problem 2 solution here (and other places). break; default: pError_Msg("Unexpected case."); } frame_timer.work_amt_set(num_bytes); // Insert additional triangle. // { pCoor v0( 1.5, 0, -3.2 ); pCoor v1( 0, 5, -5 ); pCoor v2( 9, 6, -9 ); pVect normal(cross(v0,v1,v2)); glColor3fv( color_purple ); glBegin(GL_TRIANGLES); glNormal3fv(normal); glVertex3fv(v0); glNormal3fv(normal); glVertex3fv(v1); glNormal3fv(normal); glVertex3fv(v2); glEnd(); } glColor3f(0,1,0); // This sets the text color. Don't know why. pError_Check(); frame_timer.frame_end(); glutSwapBuffers(); } int main(int argc, char **argv) { pOpenGL_Helper popengl_helper(argc,argv); Tube tube(popengl_helper); popengl_helper.rate_set(30); popengl_helper.display_cb_set(tube.render_w,&tube); return 0; }