From 13c9711b883931845a11c591d1880ce00827e1a3 Mon Sep 17 00:00:00 2001
From: ultrakatiz <ultrakatiz@gmail.com>
Date: Fri, 20 May 2022 00:11:17 +0200
Subject: [PATCH] shapes can now render with a camera
---
all.lua | 1 +
camera.lua | 35 +++++++++++++++++++++++++++++++++++
shape.lua | 21 +++++++++++++++------
transform.lua | 24 +++++++++++++++++++++++-
4 files changed, 74 insertions(+), 7 deletions(-)
create mode 100644 camera.lua
diff --git a/all.lua b/all.lua
index 3834ea8..f8b0e4f 100644
--- a/all.lua
+++ b/all.lua
@@ -3,3 +3,4 @@ require("kara3d.matrix")
require("kara3d.quaternion")
require("kara3d.transform")
require("kara3d.shape")
+require("kara3d.camera")
diff --git a/camera.lua b/camera.lua
new file mode 100644
index 0000000..d5b2108
--- /dev/null
+++ b/camera.lua
@@ -0,0 +1,35 @@
+require("kara3d.transform")
+
+-- ********** DEFINITION AND GENERIC FUNCTIONS **********
+
+camera = {class = "camera"}
+camera.__index = camera
+
+-- Creates a camera at transform t with aspect ratio a, horizontal fov f,
+-- near plane distance nd and far plane distance fd
+function camera.new(t, f, nd, fd)
+ local c = {transform = t, fov = f or 80 / 180 * math.pi,
+ near = nd or 1, far = fd or 1000000000}
+ setmetatable(c, camera)
+ return c
+end
+
+-- Clones this camera
+function camera:clone()
+ return camera.new(self.transform, self.fov, self.near, self.far)
+end
+
+-- ********** INSTANCE FUNCTIONS **********
+
+-- Returns this camera's projection * view matrix
+function camera:matrix()
+ local s = 1 / math.tan(self.fov / 2)
+ local n, f = self.near, self.far
+ local xres, yres, _, _ = aegisub.video_size()
+ local m = matrix.new(4, 4,
+ {s, 0, 0, 0,
+ 0, s, 0, 0,
+ 0, 0, (n+f) / (n-f), 2*n*f / (n-f),
+ 0, 0, 1 / xres, 0})
+ return m * self.transform:inv_matrix(true)
+end
diff --git a/shape.lua b/shape.lua
index 803e4f0..22aadec 100644
--- a/shape.lua
+++ b/shape.lua
@@ -2,6 +2,7 @@ require("kara3d.vector")
require("kara3d.matrix")
require("kara3d.quaternion")
require("kara3d.transform")
+require("kara3d.camera")
require("utils")
-- ********** DEFINITION AND GENERIC FUNCTIONS **********
@@ -36,37 +37,45 @@ end
-- Generates a line for each face of this shape, with the indicated tags
-- The boolean cull determines if the faces facing away from the screen are
-- drawn or not
-function shape:draw(subs, line, tags, cull)
+function shape:draw(subs, line, tags, cull, cam)
local l = table.copy(line)
local p = self.transform:position(true)
local r = self.transform:rotation(true)
- local m = self.transform:matrix(true)
local c = vector.cardinal(4, 4)
local layer = line.layer
+ local pv = cam and cam:matrix() or matrix.identity(4, 4)
+ local cam_inv_rot = cam and cam.transform:rotation(true):inv() or quaternion.identity()
+ local xres, yres, _, _ = aegisub.video_size()
+
+ local m = pv * self.transform:matrix(true)
+
for i = 1, #self.faces do
local face = self.faces[i]
local n = quaternion.mul_vector(r, face.normal)
+ n = quaternion.mul_vector(cam_inv_rot, n)
if not (cull and n:z() > 0) then
local vs = face.vertices
- local v = matrix.mul_vector(m, vs[#vs] + c) - p
+ local v = m * (vs[#vs] + c)
+ v = (1 / v:w()) * v
local sum = vector.zero(4)
local str = (tags and "{" .. tags .. "}" or "")
.. (face.tags and "{" .. face.tags .. "}" or "")
- .. "{\\an7\\pos(" .. p:x() .. ", " .. p:y() .. ")\\p1}"
+ .. "{\\an7\\pos(" .. (xres / 2) .. ", " .. (yres / 2) .. ")\\p1}"
.. "m " .. v:x() .. " " .. v:y() .. " "
for i = 1, #vs do
- v = matrix.mul_vector(m, vs[i] + c) - p
+ v = m * (vs[i] + c)
sum = sum + v
+ v = (1 / v:w()) * v
str = str .. "l " .. v:x() .. " " .. v:y() .. " "
end
l.text = str
-- layers must be between 0 and 9999999999
- l.layer = 500000000 + math.floor(-(p + sum):z() / #vs)
+ l.layer = 500000000 + math.floor((p + sum):z() / #vs)
l.effect = "fx"
subs.append(l)
end
diff --git a/transform.lua b/transform.lua
index e755162..b141d8f 100644
--- a/transform.lua
+++ b/transform.lua
@@ -81,9 +81,31 @@ function transform:matrix(global)
0, 0, 0, 1})
local m = translation * rotation * scale
- if (global and self.parent ~= nil) then
+ if (global and self.parent) then
m = self.parent:matrix(true) * m
end
return m
end
+
+-- Returns the inverse of the transformation matrix of this transform
+function transform:inv_matrix(global)
+ local translation = matrix.new(4, 4,
+ {1, 0, 0, -self.pos:get(1),
+ 0, 1, 0, -self.pos:get(2),
+ 0, 0, 1, -self.pos:get(3),
+ 0, 0, 0, 1})
+ local rotation = self.rot:normalized():inv():to_matrix()
+ local scale = matrix.new(4, 4,
+ {1/self.scl:get(1), 0, 0, 0,
+ 0, 1/self.scl:get(2), 0, 0,
+ 0, 0, 1/self.scl:get(3), 0,
+ 0, 0, 0, 1})
+ local m = scale * rotation * translation
+
+ if (global and self.parent) then
+ m = m * self.parent:inv_matrix(true)
+ end
+
+ return m
+end
--
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