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ylwdiogl
01-19-2014, 02:31 AM
There the question as the title i want to ask for answer, for help,ths

carsten neumann
01-19-2014, 06:13 AM
I don't think there is a way to answer your question without more details. Since OpenGL specifies a pipeline the coordinate system vertex data is in depends on the pipeline stage you are looking at, for example.

ylwdiogl
01-19-2014, 10:47 PM
I don't think there is a way to answer your question without more details. Since OpenGL specifies a pipeline the coordinate system vertex data is in depends on the pipeline stage you are looking at, for example.

Ok, i try to make it more clear ,just like that ,following:
code:
translation_matrix[16]={ 1,0,0,0,
0,1,0,0,
0,0,1,0,
12,13,14,1 }
glBegin(GL_LINE);
glVertex(12,13,14); //vertex_1
glVertex(0,13,14);
glEnd();
glPushMatrix();
glMultiMatrix(translation_matrix);
glBegin(GL_LINE);
glVertex(12,13,14); //vertex_2
glVertex(0,13,14);
glEnd();
glPopMatrix();

I want to know whether the "vertex_1" actually is the “vertex_2”

thokra
01-20-2014, 02:50 AM
I want to know whether the "vertex_1" actually is the “vertex_2”

No, if you apply translation_matrix to vertex_2 you'll get (12 + 12, 13 + 13, 14 +14) == 2 * vertex_2 == (24, 26, 28) - assuming, of course, the top of the MODELVIEW stack is actually the identity, which is nothing one can deduce from your example.