And my frame rate returned to normal, with animated characters. To fix it, instead of calling a function to animate the models, I manually inlined the code. I stared at this code for a while (more than a while actually), and after messing about a bit, it finally dawned on me what’s wrong with it. It then weights them by how much influence each bone has on the vertex. What this code does is transform the position of a vertex by up to four bones in the models structure. Gl_Position = (gc.worldToProjection * (tc.transform * vec4(position, 1.0))) Vec3 position = SkinPosition(inputPosition, inputIndex, inputIndex, bc) (ansforms * vec4(position, 1.0)) * weight.w)).xyz (ansforms * vec4(position, 1.0)) * weight.z + (ansforms * vec4(position, 1.0)) * weight.y + ((ansforms * vec4(position, 1.0)) * weight.x + Vec3 SkinPosition(vec3 position, ivec4 index, vec4 weight, BoneConstants bones) This isn’t the entire shader, just enough to get an idea of how the animation part works. It looks pretty standard and is simple code. So here’s the basic code that handles animation in GLSL. Since rendering houses and trees really only has minor differences with animated models I disabled the shader code that animates the models and the frame rate went back up to normal. And if I remove the people from my original test scene, the frame rate is over 100. The image of just trees doesn’t have any deer or people moving around. So after much debugging I determined that rendering animated models was causing the slow down. Thats a difference of 63 or so milliseconds. If I move the camera to a different location, the frame rate is 126. I’ve got the game paused so there isn’t any time spent on updates, this is just drawing. So here’s a scene, rendering on OSX, at an abysmal frame rate of 14 on a MacBook Pro. This week I’ve properly fixed the issue, and I want to record it here for myself and others to avoid this mistake. I identified the problem and made some work arounds for development to continue. A few months ago I had some interesting performance problems with OpenGL on OSX.

Banished pc game running like junk