From: Mikko Rasa Date: Sun, 13 Dec 2015 11:53:59 +0000 (+0200) Subject: Use a more 3d-y approach for generating the monitor mesh X-Git-Url: http://git.tdb.fi/?a=commitdiff_plain;h=6d10193f0bc3827089e919d41fe6af53ffe0e1a7;p=geometrycompositor.git Use a more 3d-y approach for generating the monitor mesh It's easier to grasp, especially when more corrections are implemented. The coordinates for cylinder correction are now spaced evenly by angle rather than X coordinate. This also fixes incorrect texture coordinates. --- diff --git a/source/main.c b/source/main.c index 04e6620..08be9dd 100644 --- a/source/main.c +++ b/source/main.c @@ -465,49 +465,75 @@ void update_monitor_vertices(CompositedScreen *screen, CompositedMonitor *monito unsigned x, y; unsigned i; float aspect; - float cyl_w_sq; + float cyl_radius; + float cyl_arc; float sin_ksv; float cos_ksv; + float distance; + float eye[3]; + float look[3]; t = monitor->tessellation; data_size = (t+1)*(t+1)*4*sizeof(float); vertex_data = (float *)malloc(data_size); + aspect = (float)monitor->width/monitor->height; - cyl_w_sq = 0.25f-(0.5f-monitor->cylinder_depth)*(0.5f-monitor->cylinder_depth); + + if(monitor->cylinder_depth) + { + cyl_radius = (monitor->cylinder_depth*monitor->cylinder_depth+0.25f)/(2.0f*monitor->cylinder_depth); + cyl_arc = 2.0f*asin(0.5f/cyl_radius); + } + sin_ksv = monitor->keystone_vertical/sqrt(1.0f+monitor->keystone_vertical*monitor->keystone_vertical); cos_ksv = sqrt(1.0f-sin_ksv*sin_ksv); + distance = monitor->perspective+sin_ksv*((sin_ksv>0)-monitor->vertical_center)/aspect; + + eye[0] = 0.0f; + eye[1] = (monitor->vertical_center-0.5f)/aspect+sin_ksv*distance; + eye[2] = cos_ksv*distance; + + look[0] = 0.0f; + look[1] = -sin_ksv; + look[2] = -cos_ksv; + for(y=0; y<=t; ++y) for(x=0; x<=t; ++x) { - float xf, yf, z, rz; - float scale; float *v; - xf = (float)x/t; - yf = (float)y/t; - - v = vertex_data+(y*(t+1)+x)*4; - v[2] = (monitor->x+xf*monitor->width)/screen->width; - v[3] = ((float)screen->height-monitor->y-monitor->height+yf*monitor->height)/screen->height; - - z = sqrt(0.25f-(xf-0.5f)*(xf-0.5f)*4.0f*cyl_w_sq)-0.5f+monitor->cylinder_depth; - if(monitor->keystone_vertical>0) + v = vertex_data+(y*(t+1)+x)*3; + v[0] = (float)x/t-0.5f; + v[1] = ((float)y/t-0.5f)/aspect; + v[2] = 0; + if(monitor->cylinder_depth) { - rz = (1.0f-yf)/aspect*sin_ksv+z*cos_ksv; - yf = 1.0f-((1.0f-yf)*cos_ksv-z*aspect*sin_ksv); - z = rz; + v[2] = (1.0f-cos(v[0]*cyl_arc))*cyl_radius-monitor->cylinder_depth; + v[0] = sin(v[0]*cyl_arc)*cyl_radius; } - else if(monitor->keystone_vertical<0) - { - rz = z*cos_ksv-yf/aspect*sin_ksv; - yf = yf*cos_ksv+z*aspect*sin_ksv; - z = rz; - } - scale = monitor->perspective/(monitor->perspective+z); - v[0] = 0.5f+(xf-0.5f)*scale; - v[1] = monitor->vertical_center+(yf-monitor->vertical_center)*scale; } + + for(y=t; y<=t; --y) + for(x=t; x<=t; --x) + { + float *v; + float px, py, pz; + float scale; + + v = vertex_data+(y*(t+1)+x)*3; + px = v[0]-eye[0]; + py = (v[0]-eye[0])*look[0] - (v[1]-eye[1])*look[2] + (v[2]-eye[2])*look[1]; + pz = (v[0]-eye[0])*look[0] + (v[1]-eye[1])*look[1] + (v[2]-eye[2])*look[2]; + scale = monitor->perspective/pz; + + v = vertex_data+(y*(t+1)+x)*4; + v[0] = px*scale+0.5f; + v[1] = py*aspect*scale+monitor->vertical_center; + v[2] = (monitor->x+(float)x*monitor->width/t)/screen->width; + v[3] = 1.0f-(monitor->y+(1.0f-(float)y/t)*monitor->height)/screen->height; + } + glBindBuffer(GL_ARRAY_BUFFER, monitor->vertex_buffer); glBufferData(GL_ARRAY_BUFFER, data_size, vertex_data, GL_STATIC_DRAW); glBindBuffer(GL_ARRAY_BUFFER, 0);