From 9dc5a7649762f272769ab97f896483411d70e0f9 Mon Sep 17 00:00:00 2001
From: Martin Fiedler <keyj@emphy.de>
Date: Thu, 2 Jul 2020 22:07:01 +0200
Subject: [PATCH] explicitly disable face culling before drawing lines

Normally, this shouldn't matter, and on almost all
OpenGL drivers out there, it really doesn't, but
the Raspberry Pi 4's "V3D" Mesa driver behaves
differently: It simply won't draw any lines as long
as GL_CULL_FACE is enabled, so we need to disable
it.
---
 similar/arch/ogl/ogl.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/similar/arch/ogl/ogl.cpp b/similar/arch/ogl/ogl.cpp
index f7e8a6c72..8f3407ca4 100644
--- a/similar/arch/ogl/ogl.cpp
+++ b/similar/arch/ogl/ogl.cpp
@@ -554,6 +554,7 @@ void g3_draw_line(grs_canvas &canvas, const g3s_point &p0, const g3s_point &p1,
   
 	ogl_client_states<int, GL_VERTEX_ARRAY, GL_COLOR_ARRAY> cs;
 	OGL_DISABLE(TEXTURE_2D);
+	glDisable(GL_CULL_FACE);
 	color_r = PAL2Tr(c);
 	color_g = PAL2Tg(c);
 	color_b = PAL2Tb(c);