ear All:
I have a question related to ModelView Matirx Operation,
and would like to know how does OpenGL perform the operation.
Let say my current modelView Matrix is
T0 =1.000000 T1 =0.000000 T2 =0.000000 T3 =0.000000
T4 =0.000000 T5 =1.000000 T6 =0.000000 T7 =0.000000
T8 =0.000000 T9 =0.000000 T10=1.000000 T11=0.000000
T12=3.320000 T13=0.080000 T14=-60.935867 T15=1.000000
and then I specify the glScale command by glScaled(0.313486, 0.313486, 0.313486);
what will the modelview matrix look like? I use glGetDoublev(GL_MODELVIEW_MATRIX,modelMatrix);
and print out the modelView Matrix, it is shown as follows:
T0 =0.313486 T1 =0.000000 T2 =0.000000 T3 =0.000000
T4 =0.000000 T5 =0.313486 T6 =0.000000 T7 =0.000000
T8 =0.000000 T9 =0.000000 T10=0.313486 T11=0.000000
T12=3.320000 T13=0.080000 T14=-60.935867 T15=1.000000
Then if I specify glTranslated(-31.789, -22.129, 60.935867);
the modelView Matrix becomes the following:
T0 =0.313486 T1 =0.000000 T2 =0.000000 T3 =0.000000
T4 =0.000000 T5 =0.313486 T6 =0.000000 T7 =0.000000
T8 =0.000000 T9 =0.000000 T10=0.313486 T11=0.000000
T12=-6.645412 T13=-6.857136 T14=-41.833313 T15=1.000000
Why glTranslated(-31.789, -22.129, 60.935867) command
results in T12=-6.645412 T13=-6.857136 T14=-41.833313 ??
Thanks for any help.
Robert tyyu@ksts.seed.net.tw