From a27a62fff040240389ffa5a25254206044185588 Mon Sep 17 00:00:00 2001
From: outfrost <kotlet.bahn@gmail.com>
Date: Wed, 27 May 2020 02:51:55 +0200
Subject: [PATCH] Compute world space transforms for rendering

---
 src/engine/render.c | 12 +++++++-----
 src/main.c          |  4 ----
 2 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/src/engine/render.c b/src/engine/render.c
index 34c493a..0cfc49f 100644
--- a/src/engine/render.c
+++ b/src/engine/render.c
@@ -11,7 +11,7 @@ const Scene* cameraAnchor;
 
 static const float AXIS_RADIUS = 5.0f;
 
-static void renderScene(const Scene*);
+static void renderScene(const Scene*, const Transform baseTransform);
 static void setupCamera();
 static void moveCameraTo(const Scene* scene);
 static void drawAxes();
@@ -47,7 +47,7 @@ void renderFrame() {
 	setupCamera();
 	moveCameraTo(cameraAnchor);
 
-	renderScene(currentScene);
+	renderScene(currentScene, identity());
 
 	glFlush();
 	glutSwapBuffers();
@@ -55,13 +55,15 @@ void renderFrame() {
 	glutPostRedisplay();
 }
 
-void renderScene(const Scene* scene) {
+static void renderScene(const Scene* scene, const Transform baseTransform) {
 	if (!scene) {
 		return;
 	}
 
+	Transform transform = multiply(scene->transform, baseTransform);
+
 	glMatrixMode(GL_MODELVIEW);
-	glLoadTransposeMatrixf((const GLfloat*) &scene->transform);
+	glLoadTransposeMatrixf((const GLfloat*) &transform);
 
 	glDisable(GL_LIGHTING);
 	drawAxes();
@@ -76,7 +78,7 @@ void renderScene(const Scene* scene) {
 	}
 
 	for (size_t i = 0; i < scene->numChildren; ++i) {
-		renderScene(scene->children[i]);
+		renderScene(scene->children[i], transform);
 	}
 }
 
diff --git a/src/main.c b/src/main.c
index fa9ed02..7372d8e 100644
--- a/src/main.c
+++ b/src/main.c
@@ -48,10 +48,6 @@ int main(int argc, char** argv) {
 		logWarning("Could not enable vsync (extensions not supported)");
 	}
 	
-	GLint maxModelviewStackDepth;
-	glGetIntegerv(GL_MAX_MODELVIEW_STACK_DEPTH, &maxModelviewStackDepth);
-	logDebug("GL_MAX_MODELVIEW_STACK_DEPTH: %d", maxModelviewStackDepth);
-	
 	glutDisplayFunc(renderFrame);
 	glutReshapeFunc(resizeStage);
 	//glutKeyboardFunc(key_pressed);
-- 
2.44.0