From 0d765be40336decc966932e0143fe9496f3eab4b Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Sun, 18 Apr 2021 20:21:54 +0300
Subject: [PATCH] Use a separate shadow caster renderable for ShadowMap

This makes the configuration more flexible.  For example it's possible
to use a Sequence to define which tag to use for the shadow pass.
---
 source/effects/shadowmap.cpp | 29 +++++++++++++++++++++++------
 source/effects/shadowmap.h   |  7 ++++++-
 2 files changed, 29 insertions(+), 7 deletions(-)

diff --git a/source/effects/shadowmap.cpp b/source/effects/shadowmap.cpp
index 0af93271..639a3525 100644
--- a/source/effects/shadowmap.cpp
+++ b/source/effects/shadowmap.cpp
@@ -13,15 +13,31 @@ using namespace std;
 namespace Msp {
 namespace GL {
 
+ShadowMap::ShadowMap(Resources &resources, unsigned s, Renderable &r, const Light &l, Renderable &c):
+	Effect(r),
+	light(l),
+	shadow_caster(c),
+	sampler(resources.get<Sampler>("_linear_clamp_shadow.samp"))
+{
+	init(s);
+}
+
 ShadowMap::ShadowMap(Resources &resources, unsigned s, Renderable &r, const Light &l):
 	Effect(r),
-	size(s),
 	light(l),
-	sampler(resources.get<Sampler>("_linear_clamp_shadow.samp")),
-	radius(1),
-	depth_bias(4),
-	rendered(false)
+	shadow_caster(r),
+	sampler(resources.get<Sampler>("_linear_clamp_shadow.samp"))
 {
+	init(s);
+}
+
+void ShadowMap::init(unsigned s)
+{
+	size = s;
+	radius = 1;
+	depth_bias = 4;
+	rendered = false;
+
 	depth_buf.storage(DEPTH_COMPONENT32F, size, size, 1);
 	fbo.attach(DEPTH_ATTACHMENT, depth_buf, 0);
 	fbo.require_complete();
@@ -58,6 +74,7 @@ void ShadowMap::setup_frame(Renderer &renderer)
 
 	rendered = true;
 	renderable.setup_frame(renderer);
+	shadow_caster.setup_frame(renderer);
 
 	shadow_camera.set_object_matrix(*light.get_matrix());
 	shadow_camera.set_position(target);
@@ -78,7 +95,7 @@ void ShadowMap::setup_frame(Renderer &renderer)
 	Renderer::Push push(renderer);
 	renderer.set_camera(shadow_camera);
 
-	renderer.render(renderable, "shadow");
+	renderer.render(shadow_caster);
 }
 
 void ShadowMap::finish_frame()
diff --git a/source/effects/shadowmap.h b/source/effects/shadowmap.h
index d7b4eef9..5d8bf509 100644
--- a/source/effects/shadowmap.h
+++ b/source/effects/shadowmap.h
@@ -25,6 +25,7 @@ class ShadowMap: public Effect
 private:
 	unsigned size;
 	const Light &light;
+	Renderable &shadow_caster;
 	Framebuffer fbo;
 	Camera shadow_camera;
 	Matrix shadow_matrix;
@@ -37,8 +38,12 @@ private:
 	bool rendered;
 
 public:
-	ShadowMap(Resources &, unsigned, Renderable &, const Light &);
+	ShadowMap(Resources &, unsigned, Renderable &, const Light &, Renderable &);
+	DEPRECATED ShadowMap(Resources &, unsigned, Renderable &, const Light &);
+private:
+	void init(unsigned);
 
+public:
 	/** Sets the ShadowMap target point and radius.  The transformation matrix is
 	computed so that a sphere with the specified parameters will be completely
 	covered by the ShadowMap. */
-- 
2.43.0