haloopdy/3dtrial
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Back to rendering somewhat properly again

Browse Source
This commit is contained in:
Carlos Sanchez 2024-08-04 16:12:18 -04:00
parent 27874d042f
commit 48366274c3
3 changed files with 202 additions and 64 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

23
renderer3/hrend/math.go
View File

@ -132,10 +132,8 @@ func (m *Mat44f) SetProjection(fov float32, aspect float32, near float32, far fl
m.Set(0, 0, near/right)
m.Set(1, 1, near/top)
m.Set(2, 2, -(far+near)/(far-near))
//m.Set(2, 2, -(far)/(far-near))
m.Set(3, 2, -1)
m.Set(2, 3, -(2*far*near)/(far-near))
//m.Set(2, 3, -(far*near)/(far-near))
}
func (m *Mat44f) SetViewport(tl Vec3f, br Vec3f) { //width, height, depth int) {
@ -237,8 +235,25 @@ func (m *Mat44f) SetLookAt(from *Vec3f, to *Vec3f, up *Vec3f) {
m.Set(2, 3, from.Z)
}
// Multiply the given point by our vector. Remember this is row-major order
func (m *Mat44f) MultiplyPoint3(p Vec3f) Vec3f {
// Multiply the given point by our vector. Remember this is row-major order.
// Point is NOT scaled back
func (m *Mat44f) MultiplyPoint3(p Vec3f) (Vec3f, float32) {
var out Vec3f
// We hope very much that Go will optimize the function calls for us,
// along with computing the constants.
out.X = p.X*m.Get(0, 0) + p.Y*m.Get(0, 1) + p.Z*m.Get(0, 2) + m.Get(0, 3)
out.Y = p.X*m.Get(1, 0) + p.Y*m.Get(1, 1) + p.Z*m.Get(1, 2) + m.Get(1, 3)
out.Z = p.X*m.Get(2, 0) + p.Y*m.Get(2, 1) + p.Z*m.Get(2, 2) + m.Get(2, 3)
w := p.X*m.Get(3, 0) + p.Y*m.Get(3, 1) + p.Z*m.Get(3, 2) + m.Get(3, 3)
// out.X /= w
// if w != 1 {
// out.Y /= w
// out.Z /= w
// }
return out, w
}
func (m *Mat44f) MultiplyPoint3Conventional(p Vec3f) Vec3f {
var out Vec3f
// We hope very much that Go will optimize the function calls for us,
// along with computing the constants.

129
renderer3/hrend/render.go
View File

@ -2,8 +2,29 @@ package hrend
import (
// "log"
// "math"
)
type ObjectDef struct {
Model *ObjModel
Texture Framebuffer // This needs to go somewhere else eventually!
Pos Vec3f
LookVec Vec3f
Scale float32
Lighting bool
}
func NewObjectDef(model *ObjModel, texture Framebuffer) *ObjectDef {
result := ObjectDef{
Model: model,
Texture: texture,
LookVec: Vec3f{X: 0, Y: 0, Z: -1},
Scale: 1,
Lighting: true,
}
return &result
}
// Figure out the minimum bounding box for a triangle defined by
// these vertices. Returns the top left and bottom right points,
// inclusive
@ -117,10 +138,10 @@ func TriangleTextured(fb *RenderBuffer, texture Framebuffer, intensity float32,
//boundsBRf.Z < 0 || boundsTLf.Z > 1 {
return
}
if boundsBRf.Z < 0 || boundsTLf.Z > 1 {
//log.Print(boundsTLf, boundsBRf)
return
}
// if boundsBRf.Z < 0 || boundsTLf.Z > 1 {
// //log.Print(boundsTLf, boundsBRf)
// return
// }
v0 := v0v.Pos.ToVec2i()
v1 := v1v.Pos.ToVec2i()
v2 := v2v.Pos.ToVec2i()
@ -212,3 +233,103 @@ func TriangleTextured(fb *RenderBuffer, texture Framebuffer, intensity float32,
w2_y += w2_yi
}
}
//func PerspectiveAndClip(//o * ObjectDef, screenmat *Mat44f, width int, height int) {
// Return true if the face should be culled
func BackfaceCull(v1, v2, v3 Vec3f) bool {
return (v1.X-v2.X)*(v3.Y-v2.Y)-(v1.Y-v2.Y)*(v3.X-v2.X) >= 0
// This is what it essentially is
// e1 := v1.Sub(&v2)
// e2 := v1.Sub(&v3)
// // If viewing front face, it should be pointing in the positive z direction
// return e1.CrossProduct(e2).Z <= 0
// But we know we can just use x and y since this is post projection
//l1 := f[2].Pos.Sub(&f[0].Pos)
//n := l1.CrossProduct(f[1].Pos.Sub(&f[0].Pos))
}
// func TriangleTextured(fb *RenderBuffer, texture Framebuffer, intensity float32, v0v Vertex, v1v Vertex, v2v Vertex) {
// func PerspectiveAndClip(infaces []Facef, matrix3d *Mat44f, outfaces []Facef) {
func PerspectiveAndClip(face Facef, matrix3d *Mat44f) []Facef { //, outfaces []Facef) {
//var facei = 0
outfaces := make([]Facef, 0, 2)
var sc Facef
var w [3]float32
var d [3]float32
outers := make([]int, 0, 3)
// miny := float32(math.MaxFloat32)
// minyx := float32(math.MaxFloat32)
// minyi := 0
//var modelmat Mat44f
//var intensity float32
//modelmat.SetLookAt(&o.Pos, o.Pos.Add(&o.LookVec), &camup)
//modelmat.ScaleSelf(o.Scale)
//matrix3d := modelmat.Multiply(screenmat)
//for _, f := range infaces {
for i := range 3 {
sc[i] = face[i]
sc[i].Pos, w[i] = matrix3d.MultiplyPoint3(face[i].Pos)
d[i] = sc[i].Pos.Z + w[i]
if d[i] < 0 {
outers = append(outers, i)
}
// if sc[i].Pos.Y < miny || sc[i].Pos.Y < {
// miny = sc[i].Pos.Y
// minyi = i
// }
//miny = min(miny, sc[i].Pos.Y)
//minz = min(minz, sc[i].Pos.Z)
//maxz = max(maxz, sc[i].Pos.Z)
}
// Just to test: reject any that have points outside. We don't clip
if len(outers) > 0 {
return outfaces
} else {
for i := range 3 {
//sc[i]
if w[i] != 1 {
sc[i].Pos.X /= w[i]
sc[i].Pos.Y /= w[i]
sc[i].Pos.Z /= w[i]
}
}
// Backface culling: no need to do anything with triangles facing the wrong way
if !BackfaceCull(sc[0].Pos, sc[1].Pos, sc[2].Pos) {
outfaces = append(outfaces, sc)
}
//outfaces[facei] = sc
//facei += 1
return outfaces
}
// TODO: Now that we're here doing it like this, might as well remove faces
// that are fully outside the other clipping zones. No need to do actual clipping...
// just full rejections. This saves a BIT of processing... though not much
// log.Print(o.Model.Faces[0][0].Pos, o.Model.Faces[0][1].Pos, o.Model.Faces[0][2].Pos)
// log.Print(sc[0].Pos, sc[1].Pos, sc[2].Pos)
// log.Print(matrix3d)
// for i := range 3 {
// // Perspective divide (?) and screen coord
// sc[i].Pos.ViewportSelf(width, height)
// }
// //log.Print(sc[0].Pos, sc[1].Pos, sc[2].Pos, matrix3d)
// if o.Lighting {
// l1 := f[2].Pos.Sub(&f[0].Pos)
// n := l1.CrossProduct(f[1].Pos.Sub(&f[0].Pos))
// n = n.Normalize()
// // light = lookvec // use this for weird things
// intensity = n.MultSimp(&light)
// if intensity < 0 {
// intensity = 0
// }
// intensity = (intensity + float32(*minlight)) / (1 + float32(*minlight))
// } else {
// intensity = 1.0
// }
// TriangleTextured(&rb, o.Texture, intensity, sc[0], sc[1], sc[2])
//}
}

80
renderer3/main.go
View File

@ -32,25 +32,25 @@ func must(err error) {
}
}
type ObjectDef struct {
Model *hrend.ObjModel
Texture hrend.Framebuffer // This needs to go somewhere else eventually!
Pos hrend.Vec3f
LookVec hrend.Vec3f
Scale float32
Lighting bool
}
func NewObjectDef(model *hrend.ObjModel, texture hrend.Framebuffer) *ObjectDef {
result := ObjectDef{
Model: model,
Texture: texture,
LookVec: hrend.Vec3f{X: 0, Y: 0, Z: -1},
Scale: 1,
Lighting: true,
}
return &result
}
// type ObjectDef struct {
// Model *hrend.ObjModel
// Texture hrend.Framebuffer // This needs to go somewhere else eventually!
// Pos hrend.Vec3f
// LookVec hrend.Vec3f
// Scale float32
// Lighting bool
// }
//
// func NewObjectDef(model *hrend.ObjModel, texture hrend.Framebuffer) *ObjectDef {
// result := ObjectDef{
// Model: model,
// Texture: texture,
// LookVec: hrend.Vec3f{X: 0, Y: 0, Z: -1},
// Scale: 1,
// Lighting: true,
// }
// return &result
// }
func loadObject(name string) (*hrend.ObjModel, hrend.Framebuffer) {
ofile := filepath.Join("../", name+".obj")
@ -126,7 +126,7 @@ func CameraInput(yaw, pitch float32) (float32, float32, hrend.Vec3f) {
// translate the new camera movement based on the yaw
var moverot hrend.Mat44f
moverot.SetRotationY(-yaw)
newcamtrans = moverot.MultiplyPoint3(newcamtrans)
newcamtrans = moverot.MultiplyPoint3Conventional(newcamtrans)
return yaw, pitch, newcamtrans
}
@ -183,7 +183,7 @@ func main() {
// Generate world
wtexraw := Checkerboard([]color.Color{color.RGBA{R: 0, G: 255, B: 0, A: 255}, color.RGBA{R: 50, G: 150, B: 0, A: 255}}, 32)
wtex := hrend.NewTexture(wtexraw, 1)
world := FlatTerrain(1)
world := FlatTerrain(10)
// Generate skybox
skyraw := Gradient1px(color.RGBA{R: 100, G: 100, B: 255, A: 255}, color.RGBA{R: 255, G: 255, B: 255, A: 255}, 32)
@ -199,13 +199,13 @@ func main() {
}
// And the actual objects for the scene. We also put the world in there
objects := make([]*ObjectDef, 0)
objects = append(objects, NewObjectDef(world, wtex))
objects = append(objects, NewObjectDef(sky, skytex)) // the actual skybox
objects := make([]*hrend.ObjectDef, 0)
objects = append(objects, hrend.NewObjectDef(world, wtex))
objects = append(objects, hrend.NewObjectDef(sky, skytex)) // the actual skybox
skyobj := objects[len(objects)-1]
skyobj.Scale = 50
skyobj.Lighting = false
objects = append(objects, NewObjectDef(models[1], textures[1]))
objects = append(objects, hrend.NewObjectDef(models[1], textures[1]))
objects[len(objects)-1].Pos.Y += 1
objects[len(objects)-1].Pos.Z -= 2
@ -243,26 +243,27 @@ func main() {
}
}
var sc [3]hrend.Vertex
//var faces []hrend.Facef //[3]hrend.Vertex
var modelmat hrend.Mat44f
var intensity float32
var minz = float32(math.MaxFloat32)
var maxz = float32(-math.MaxFloat32)
//var minz = float32(math.MaxFloat32)
//var maxz = float32(-math.MaxFloat32)
for _, o := range objects {
// Create the final matrix
modelmat.SetLookAt(&o.Pos, o.Pos.Add(&o.LookVec), &camup)
modelmat.ScaleSelf(o.Scale)
matrix3d := modelmat.Multiply(screenmat)
for _, f := range o.Model.Faces {
for i := range 3 {
sc[i] = f[i]
sc[i].Pos = matrix3d.MultiplyPoint3(f[i].Pos)
minz = min(minz, sc[i].Pos.Z)
maxz = max(maxz, sc[i].Pos.Z)
}
log.Print(o.Model.Faces[0][0].Pos, o.Model.Faces[0][1].Pos, o.Model.Faces[0][2].Pos)
log.Print(sc[0].Pos, sc[1].Pos, sc[2].Pos)
log.Print(matrix3d)
for _, sc := range hrend.PerspectiveAndClip(f, matrix3d) {
// for i := range 3 {
// sc[i] = f[i]
// sc[i].Pos = matrix3d.MultiplyPoint3(f[i].Pos)
// minz = min(minz, sc[i].Pos.Z)
// maxz = max(maxz, sc[i].Pos.Z)
// }
// log.Print(o.Model.Faces[0][0].Pos, o.Model.Faces[0][1].Pos, o.Model.Faces[0][2].Pos)
// log.Print(sc[0].Pos, sc[1].Pos, sc[2].Pos)
// log.Print(matrix3d)
for i := range 3 {
// Perspective divide (?) and screen coord
sc[i].Pos.ViewportSelf(*width, *height)
@ -282,10 +283,11 @@ func main() {
intensity = 1.0
}
hrend.TriangleTextured(&rb, o.Texture, intensity, sc[0], sc[1], sc[2])
break // only render one face
}
//break // only render one face
//hrend.TriangleFlat(&rb, hrend.Col2Uint(byte(255*intensity), byte(255*intensity), byte(255*intensity)), sc[0].Pos, sc[1].Pos, sc[2].Pos)
}
break // only render one object
//break // only render one object
}
//log.Print(minz, maxz)