rexguo

04-13-2009, 09:29 PM

Here's a pretty basic question but may not have a good

solution, so I wanna find out what's the generally

accepted solution.

Scenario:

Imagine 2 cubes, A and B. A is transform parent of B.

In a certain frame, B is spatially in front of A. That

is, B's z-coord is less than A's.

Question:

To avoid overdraw, we sort front to back, thus drawing

B first, then A.

But if we want to do all transforms *in OpenGL*,

without duplicating the calcs in software, how do we

maintain B's transform matrix, since you have to first

specify A's transform first?

In other words, the rendering order is B then A, but

the transform order is A then B. What's the generally

accepted solution here? Thanks!

.rex

solution, so I wanna find out what's the generally

accepted solution.

Scenario:

Imagine 2 cubes, A and B. A is transform parent of B.

In a certain frame, B is spatially in front of A. That

is, B's z-coord is less than A's.

Question:

To avoid overdraw, we sort front to back, thus drawing

B first, then A.

But if we want to do all transforms *in OpenGL*,

without duplicating the calcs in software, how do we

maintain B's transform matrix, since you have to first

specify A's transform first?

In other words, the rendering order is B then A, but

the transform order is A then B. What's the generally

accepted solution here? Thanks!

.rex