From 45e3513ed3fe52f878dba3c35aa5289df3713ac1 Mon Sep 17 00:00:00 2001
From: Mark <mark@betalupi.com>
Date: Sat, 13 Jan 2024 18:57:02 -0800
Subject: [PATCH] Minor shader fixes

---
 crates/render/shaders/object.wgsl   | 12 ++++++++----
 crates/render/shaders/particle.wgsl |  6 ++++--
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/crates/render/shaders/object.wgsl b/crates/render/shaders/object.wgsl
index 8d4f4eb..a694ebc 100644
--- a/crates/render/shaders/object.wgsl
+++ b/crates/render/shaders/object.wgsl
@@ -30,7 +30,10 @@ var sampler_array: binding_array<sampler>;
 
 fn transform_vertex(obj: ObjectData, vertex_position: vec2<f32>, sprite_index: u32) -> vec4<f32> {
 	// Object scale
-	let scale = obj.size / (global_data.camera_zoom.x * obj.zpos);
+	var scale: f32 = obj.size / (global_data.camera_zoom.x * obj.zpos);
+	if obj.is_child == 1u {
+		scale /= objects[obj.parent].zpos;
+	}
 
 	// Apply scale and sprite aspect
 	// Note that our mesh starts centered at (0, 0). This is important!
@@ -70,14 +73,15 @@ fn transform_vertex(obj: ObjectData, vertex_position: vec2<f32>, sprite_index: u
 	}
 
 	if obj.is_child == u32(1) {
+
+		let parent = objects[obj.parent];
+
 		// Apply translation relative to parent
 		// Note that obj.zpos is ignored
 		pos = pos + vec2(
 			obj.xpos / (global_data.camera_zoom.x / 2.0) / global_data.window_aspect.x,
 			obj.ypos / (global_data.camera_zoom.x / 2.0)
-		);
-
-		let parent = objects[obj.parent];
+		) / parent.zpos;
 
 		// Apply parent's rotation
 		pos = mat2x2(
diff --git a/crates/render/shaders/particle.wgsl b/crates/render/shaders/particle.wgsl
index 9164209..681f1c0 100644
--- a/crates/render/shaders/particle.wgsl
+++ b/crates/render/shaders/particle.wgsl
@@ -66,9 +66,11 @@ fn vertex_main(
 		vertex.position.x * scale * global_sprites[instance.sprite_index].aspect,
 		vertex.position.y * scale
 	);
+
+	// Correct angle, since sprites point north and zero degrees is east
 	pos = mat2x2(
-		vec2(cos(angle), sin(angle)),
-		vec2(-sin(angle), cos(angle))
+		vec2(cos(angle - 1.5708), sin(angle - 1.5708)),
+		vec2(-sin(angle - 1.5708), cos(angle - 1.5708))
 	) * pos;
 
 	var trans: vec2<f32> = (instance.position + (instance.velocity * age) - global_data.camera_position);