due to escalation of dire situation with sole developer of this library development is on hold with no projectable end date effective immediately
nimsgp / libnimsgp is a software-based 3D rendering library, focussed primarily on providing usage paradigms similar to GPU-accelerated APIs
The purpose of this library is for usage on operating systems and computers without access 3D acceleration, such as(respectively) Haiku and most riscv computers.
- Debian 10 x86_64 (nim 1.4.2)
- Haiku x86_64 (nim 1.6.0)
shading sublanguage:
- Position/Transform programs
- Make 3D Pixel programs better (how?)
- Implement arbitrary attachments
- 2D Pixel programs (for backgrounds)
- Alpha-check programs (for binary alpha/pixel culling)
- Texture attachment system
main render api:
- Partial transparency recognition
- Different optimized draw procs
- Make more culling subalgorithms (
pixelchoose.nim) available - Optimize included (experimental) interpolation system
- Faster everything
- Optimized data structures
- Faster, naturally-vectorizable, traversal algs
- Binary alpha-based culling (see shading list)
- "Easy API" convenience procs
externals:
- SDL2 integrations (working but slow and not yet released)
- GLFW integrations (no work done)
- Reference renderer (current skeleton included, otherwise no work)
Follows is a bit of usage instruction. The code has explanatory comments in places in case anything needs clarification.
This file contains every type used by the defined parts of the render functionality. If you're connecting into the render functions in a piece of code you want to import this file and understand the things it does:
triBBOXspace creates a 3-dimensional floating point bounding box
of the triangle entered into it, with no "outer bounds", in whatever
coordinate space the triangle is passed to it in.
triBBOXscreen on the other hand, creates a 2-dimensional uint16
bounding box of the triangle entered into it, in final screen space,
assuming the triangle has already been transformed into such.
this is effectively only here for use in draw functions, but go mad.
collectTri reads a container holding array-relative positions of
three points on a triangle, often called an "element collection".
All of the other procs beginning with collect do the same thing,
but for different final data structures, meant for use in different
parts of the implemented renderer.
clearDepthBuff clears a depth buffer by replacing every position
contained within it with positive infinity.
clearScalarBuff more general version of clearDepthBuff which
instead replaces the positions with a predefined value. Useful
in replacement of the other one to implement natural clipping distance.
triToScreen I literally forgot I implemented this until just now,
writing this document. Huh. Coulda used that in a few spots. Turns
a triangle in normalized device coordinates into a triangle in screen
coordinates. Thinking about it, not terribly useful as models are
meant to be transformed all-at-once before draw instead of one at
a time in the draw loop. Consider it deprecated unless someone finds
a use for it I guess.
lerp two (overloaded) procs that perform linear interpolation.
lerpCol lerp but for 24bpp colour types. might make an overload
for the 64bpp colour type as well. Kind of ridiculously slow, though.
terp couldn't think of a name, estimates a 2d point's position
on a triangle in normalized triangular coordinates, for use in
interpolation. Likely can be done faster. Keystone function of
the experimental interpolation alg in this library, theoretically
can be used to increase speed of extremely large amounts of
triangular interpolations, given proper usage of the coordinates
and proper implementation of the "terp" function (to come)
tripleEdgeFunc for testing if a point falls inside of a triangle.
depthEstimate uses "terp" values to estimate the depth at a pixel.
seems to be accurate as far as I've tested to now.
triEstimate and triEstimateCol are depthEstimate but for
interpolating attachments.
depthTest is a generic inlineable for testing if the current pixel
is in front of the pixel in the image.
visTestTRANSP scratch pre-implementation of a needed proc for
binary alpha. currently not used.
visTestOPAQ actually used visibility test, note this also runs the
depth estimator and sets your depth value. Reimpliment if you need
it not to.
this file is a mess
items iterator. an iterator for screenspace bounding box's
contained pixels.
defaultBackgroundO included method of writing a render background.
yes this is equiv to glClear(GL_COLOR_BIT) technically. shup
defaultBackgroundI same thing but for the 64bpp internal buffer
type.
interiorToOuterBufferNT horrible implementation of a cross-precision
copy from the interior buffer type to the one meant to write to screen.
please only run this once per frame I beg of you, it's so slow.
drawReadyElements draws a model as provided by an element buffer.
probably really terrible, I've been awake for 14 hours and have
put too much work into that proc tonight so I'll figure it out later.
call structure is likely nightmarish.
defaultTransformerPersp transforms a model's entire point buffer
into perspective space. requires usage and understanding of GLM.
defaultTransformerFlat above proc but into orthoganal space.
defTransNormal humorous disobedience of naming conventions,
transforms a model's normal buffer into its corect world position.
uhhhh this was supposed to be a data structures file but instead contains texturing functions
oops i guess
implements important functions from the 3d api in more efficient forms for 2d rendering. only one actually new function.
line2D creates a line in the same space as the input data.
... by faking it by making a triangle cause I don't want to implement
a proper linealg right now. watch for return types or alternate procs
in later versions of the API if you use this.
safer to just ignore this folder has anything in it until the shading sublanguage is properly described.
do not attempt to contact me. put things in the issue tracker. I (current lead developer Averey Vermette) am in a bad spot and don't want to waste my little socialization time I have available providing help for unfinished software.