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11.85 Sample ‘molecule’ ¶

Example of drawing molecules.

MGL code:

alpha on:light on
subplot 2 2 0 '':title 'Methane, CH_4':rotate 60 120
sphere 0 0 0 0.25 'k':drop 0 0 0 0 0 1 0.35 'h' 1 2:sphere 0 0 0.7 0.25 'g'
drop 0 0 0 -0.94 0 -0.33 0.35 'h' 1 2:sphere -0.66 0 -0.23 0.25 'g'
drop 0 0 0 0.47 0.82 -0.33 0.35 'h' 1 2:sphere 0.33 0.57 -0.23 0.25 'g'
drop 0 0 0 0.47 -0.82 -0.33 0.35 'h' 1 2:sphere 0.33 -0.57 -0.23 0.25 'g'
subplot 2 2 1 '':title 'Water, H{_2}O':rotate 60 100
sphere 0 0 0 0.25 'r':drop 0 0 0 0.3 0.5 0 0.3 'm' 1 2:sphere 0.3 0.5 0 0.25 'g'
drop 0 0 0 0.3 -0.5 0 0.3 'm' 1 2:sphere 0.3 -0.5 0 0.25 'g'
subplot 2 2 2 '':title 'Oxygen, O_2':rotate 60 120
drop 0 0.5 0 0 -0.3 0 0.3 'm' 1 2:sphere 0 0.5 0 0.25 'r'
drop 0 -0.5 0 0 0.3 0 0.3 'm' 1 2:sphere 0 -0.5 0 0.25 'r'
subplot 2 2 3 '':title 'Ammonia, NH_3':rotate 60 120
sphere 0 0 0 0.25 'b':drop 0 0 0 0.33 0.57 0 0.32 'n' 1 2
sphere 0.33 0.57 0 0.25 'g':drop 0 0 0 0.33 -0.57 0 0.32 'n' 1 2
sphere 0.33 -0.57 0 0.25 'g':drop 0 0 0 -0.65 0 0 0.32 'n' 1 2
sphere -0.65 0 0 0.25 'g'

C++ code:

void smgl_molecule(mglGraph *gr)	// example of moleculas
{
	gr->VertexColor(false);	gr->Compression(false); // per-vertex colors and compression are detrimental to transparency
	gr->DoubleSided(false); // we do not get into atoms, while rendering internal surface has negative impact on trasparency
	gr->Alpha(true);	gr->Light(true);

	gr->SubPlot(2,2,0,"");	gr->Title("Methane, CH_4");
	gr->StartGroup("Methane");
	gr->Rotate(60,120);
	gr->Sphere(mglPoint(0,0,0),0.25,"k");
	gr->Drop(mglPoint(0,0,0),mglPoint(0,0,1),0.35,"h",1,2);
	gr->Sphere(mglPoint(0,0,0.7),0.25,"g");
	gr->Drop(mglPoint(0,0,0),mglPoint(-0.94,0,-0.33),0.35,"h",1,2);
	gr->Sphere(mglPoint(-0.66,0,-0.23),0.25,"g");
	gr->Drop(mglPoint(0,0,0),mglPoint(0.47,0.82,-0.33),0.35,"h",1,2);
	gr->Sphere(mglPoint(0.33,0.57,-0.23),0.25,"g");
	gr->Drop(mglPoint(0,0,0),mglPoint(0.47,-0.82,-0.33),0.35,"h",1,2);
	gr->Sphere(mglPoint(0.33,-0.57,-0.23),0.25,"g");
	gr->EndGroup();

	gr->SubPlot(2,2,1,"");	gr->Title("Water, H_{2}O");
	gr->StartGroup("Water");
	gr->Rotate(60,100);
	gr->StartGroup("Water_O");
	gr->Sphere(mglPoint(0,0,0),0.25,"r");
	gr->EndGroup();
	gr->StartGroup("Water_Bond_1");
	gr->Drop(mglPoint(0,0,0),mglPoint(0.3,0.5,0),0.3,"m",1,2);
	gr->EndGroup();
	gr->StartGroup("Water_H_1");
	gr->Sphere(mglPoint(0.3,0.5,0),0.25,"g");
	gr->EndGroup();
	gr->StartGroup("Water_Bond_2");
	gr->Drop(mglPoint(0,0,0),mglPoint(0.3,-0.5,0),0.3,"m",1,2);
	gr->EndGroup();
	gr->StartGroup("Water_H_2");
	gr->Sphere(mglPoint(0.3,-0.5,0),0.25,"g");
	gr->EndGroup();
	gr->EndGroup();

	gr->SubPlot(2,2,2,"");	gr->Title("Oxygen, O_2");
	gr->StartGroup("Oxygen");
	gr->Rotate(60,120);
	gr->Drop(mglPoint(0,0.5,0),mglPoint(0,-0.3,0),0.3,"m",1,2);
	gr->Sphere(mglPoint(0,0.5,0),0.25,"r");
	gr->Drop(mglPoint(0,-0.5,0),mglPoint(0,0.3,0),0.3,"m",1,2);
	gr->Sphere(mglPoint(0,-0.5,0),0.25,"r");
	gr->EndGroup();

	gr->SubPlot(2,2,3,"");	gr->Title("Ammonia, NH_3");
	gr->StartGroup("Ammonia");
	gr->Rotate(60,120);
	gr->Sphere(mglPoint(0,0,0),0.25,"b");
	gr->Drop(mglPoint(0,0,0),mglPoint(0.33,0.57,0),0.32,"n",1,2);
	gr->Sphere(mglPoint(0.33,0.57,0),0.25,"g");
	gr->Drop(mglPoint(0,0,0),mglPoint(0.33,-0.57,0),0.32,"n",1,2);
	gr->Sphere(mglPoint(0.33,-0.57,0),0.25,"g");
	gr->Drop(mglPoint(0,0,0),mglPoint(-0.65,0,0),0.32,"n",1,2);
	gr->Sphere(mglPoint(-0.65,0,0),0.25,"g");
	gr->EndGroup();
	gr->DoubleSided( true ); // put back
}