From 0d12bc4156f4065ce10dc1a3ad56c010d32e4794 Mon Sep 17 00:00:00 2001
From: Carlos Sanchez <randomouscrap98@aol.com>
Date: Wed, 24 Jul 2024 19:18:42 -0400
Subject: [PATCH] Animations!

---
 tinyrender1_perspective/animation.sh | 24 ++++++++++++++++++++++++
 tinyrender1_perspective/main.go      | 17 +++++++++++------
 2 files changed, 35 insertions(+), 6 deletions(-)
 create mode 100755 tinyrender1_perspective/animation.sh

diff --git a/tinyrender1_perspective/animation.sh b/tinyrender1_perspective/animation.sh
new file mode 100755
index 0000000..77b7c4f
--- /dev/null
+++ b/tinyrender1_perspective/animation.sh
@@ -0,0 +1,24 @@
+#!/bin/sh
+
+if [ $# -ne 1 ]; then
+  echo "You must pass the basename for the animation folder"
+  exit 1
+fi
+
+echo "Building"
+go build
+mkdir -p $1
+
+echo "Running"
+
+frame=0
+for x in $(seq -3 0.1 3); do
+  ff=$(printf "%03d" $frame)
+  ./tinyrender1 "-xofs=$x" "-zofs=-1.8" "-fov=70" >"$1/$ff.ppm"
+  frame=$((frame + 1))
+done
+
+echo "Converting animation"
+
+cd $1
+convert -delay 5 -loop 0 *.ppm -resize 256x256 anim.gif
diff --git a/tinyrender1_perspective/main.go b/tinyrender1_perspective/main.go
index 2d41872..b9d50db 100644
--- a/tinyrender1_perspective/main.go
+++ b/tinyrender1_perspective/main.go
@@ -11,11 +11,11 @@ import (
 const (
 	Width      = 512
 	Height     = 512
-	FOV        = 110
+	FOV        = 70
 	NearClip   = 0.1
-	FarClip    = 2 // Because the head is so small and close
+	FarClip    = 5 // Because the head is so small and close
 	ObjectFile = "head.obj"
-	Repeat     = 1000
+	Repeat     = 1 // Because I want to see an animation
 )
 
 func must(err error) {
@@ -26,6 +26,9 @@ func must(err error) {
 
 // However flag works... idk
 var cpuprofile = flag.String("cpuprofile", "", "write cpu profile to file")
+var xofs = flag.Float64("xofs", 0, "Offset image by x")
+var zofs = flag.Float64("zofs", -1.5, "Offset image by z (should be negative)")
+var fov = flag.Float64("fov", 90, "Field of view")
 
 func main() {
 	log.Printf("Program start")
@@ -59,9 +62,10 @@ func main() {
 
 	var projection Mat44f
 	var worldToCamera Mat44f
-	projection.SetProjection(FOV, NearClip, FarClip)
+	projection.SetProjection(float32(*fov), NearClip, FarClip)
 	worldToCamera.SetIdentity()
-	worldToCamera.Set(2, 3, -1) // Get farther away from the face
+	worldToCamera.Set(0, 3, float32(*xofs)) // Let user decide how to offset x
+	worldToCamera.Set(2, 3, float32(*zofs)) // Get farther away from the face (user)
 
 	var x [3]int
 	var y [3]int
@@ -78,7 +82,8 @@ func main() {
 				fp = projection.MultiplyPoint3(fp)
 				x[i] = int((fp.X + 1) * halfwidth)
 				y[i] = hi - int((fp.Y+1)*halfheight)
-				c[i] = Col2Uint(byte(0xFF*fp.Z), byte(0xFF*fp.Z), byte(0xFF*fp.Z))
+				c[i] = 0xFFFFFF
+				//c[i] = Col2Uint(byte(0xFF*fp.Z), byte(0xFF*fp.Z), byte(0xFF*fp.Z))
 			}
 			Bresenham2(&fb, c[0], x[0], y[0], x[1], y[1])
 			Bresenham2(&fb, c[1], x[1], y[1], x[2], y[2])