Producing frames within a budget.
WHAT THE BUDGET IS
The time available per frame, determined by the target rate.
WHAT THAT MEANS
Everything must complete within that, consistently.
WHY CONSISTENCY MATTERS MORE THAN AVERAGE
Occasional long frames are perceived as stutter, which is worse than a uniformly lower rate.
WHAT CONSUMES TIME
Geometry processing Pixel shading Texture and memory bandwidth Draw call overhead Synchronisation between processor and graphics processor
WHAT REDUCES DRAW CALLS
Batching objects sharing materials Instancing, drawing many copies in one call
WHAT CULLING DOES
Avoids processing what is not visible.
WHAT LEVELS OF DETAIL PROVIDE
Simpler geometry for distant objects.
WHAT TEXTURE COMPRESSION PROVIDES
Reduced bandwidth, which is frequently the constraint.
WHAT TO PROFILE WITH
Graphics debugging tools, showing time per stage and per draw call.
WHAT TO ESTABLISH FIRST
Whether you are limited by the processor or the graphics processor.
WHY
They require entirely different remedies.
WHAT TO TEST ON
The weakest hardware you support.
