i am using the following textures as input uniforms: https://puu.sh/yIiA6/242a3e9835.png
i have two shaders:

- Shader A selects two textures from 20 (one from the first 10 and one from the second 10) based on time (in sequence), adds them together (as floats) and adds noise.

- Shader B just adds the textures from two input uniforms together (as floats).
(the floating point addition makes this look weird compared to normal additive blending, this is intended)

i have 5 draw calls:

- draw call 1 renders shader B, binding textures "Dead (1).png" and "Idle (1).png" to a new texture that is created, using framebuffer ID 2

- draw call 2 renders shader A, binding textures "Dead (1).png" through "Dead(10).png" and "Idle(1).png" through "Idle(10).png" to a new texture that is created, using framebuffer ID 1

- draw call 3 renders shader B, binding textures "Dead (1).png" and "Idle (1).png" to the screen's top-left corner, using framebuffer id 0
(this is essentially to show what SHOULD be in framebuffer 2)

- draw call 4 renders shader A, binding textures "Dead (1).png" through "Dead(10).png" and "Idle(1).png" through "Idle(10).png" to the screen's bottom-left corner, using framebuffer id 0
(this is essentially to show what SHOULD be in framebuffer 1)

- draw call 5 renders shader A, binding textures associated with framebuffers 1 and 2 to the middle-right of the screen, using framebuffer id 0

this is the resulting rendering: https://puu.sh/yIiMv/ea595fd449.mp4

if instead of creating new textures for the render buffer, i load the existing textures jump (1).png and jump (2).png i get this: https://puu.sh/yIiPX/e90541d76b.mp4

neither of these results is quite what i would expect, when applying the shader that forms the bottom-left image from two input images, to the two images on the left side...