From 2f35135743f5713ab68949271074b12f040b102e Mon Sep 17 00:00:00 2001
From: Stephan Unverwerth <s.unverwerth@serenityos.org>
Date: Thu, 16 Dec 2021 21:10:53 +0100
Subject: [PATCH] LibGL+LibSoftGPU: Add face culling state to rasterizer
 options

---
 Userland/Libraries/LibGL/SoftwareGLContext.cpp     | 12 ++++++++++++
 Userland/Libraries/LibSoftGPU/SoftwareRasterizer.h |  3 +++
 2 files changed, 15 insertions(+)

diff --git a/Userland/Libraries/LibGL/SoftwareGLContext.cpp b/Userland/Libraries/LibGL/SoftwareGLContext.cpp
index 876fad1783..76f80a6147 100644
--- a/Userland/Libraries/LibGL/SoftwareGLContext.cpp
+++ b/Userland/Libraries/LibGL/SoftwareGLContext.cpp
@@ -685,6 +685,8 @@ void SoftwareGLContext::gl_enable(GLenum capability)
     switch (capability) {
     case GL_CULL_FACE:
         m_cull_faces = true;
+        rasterizer_options.enable_culling = true;
+        update_rasterizer_options = true;
         break;
     case GL_DEPTH_TEST:
         m_depth_test_enabled = true;
@@ -750,6 +752,8 @@ void SoftwareGLContext::gl_disable(GLenum capability)
     switch (capability) {
     case GL_CULL_FACE:
         m_cull_faces = false;
+        rasterizer_options.enable_culling = false;
+        update_rasterizer_options = true;
         break;
     case GL_DEPTH_TEST:
         m_depth_test_enabled = false;
@@ -1007,6 +1011,10 @@ void SoftwareGLContext::gl_front_face(GLenum face)
     RETURN_WITH_ERROR_IF(face < GL_CW || face > GL_CCW, GL_INVALID_ENUM);
 
     m_front_face = face;
+
+    auto rasterizer_options = m_rasterizer.options();
+    rasterizer_options.front_face = face;
+    m_rasterizer.set_options(rasterizer_options);
 }
 
 void SoftwareGLContext::gl_cull_face(GLenum cull_mode)
@@ -1016,6 +1024,10 @@ void SoftwareGLContext::gl_cull_face(GLenum cull_mode)
     RETURN_WITH_ERROR_IF(cull_mode < GL_FRONT || cull_mode > GL_FRONT_AND_BACK, GL_INVALID_ENUM);
 
     m_culled_sides = cull_mode;
+
+    auto rasterizer_options = m_rasterizer.options();
+    rasterizer_options.culled_sides = cull_mode;
+    m_rasterizer.set_options(rasterizer_options);
 }
 
 GLuint SoftwareGLContext::gl_gen_lists(GLsizei range)
diff --git a/Userland/Libraries/LibSoftGPU/SoftwareRasterizer.h b/Userland/Libraries/LibSoftGPU/SoftwareRasterizer.h
index 94efddd0f3..2e52d7b3c8 100644
--- a/Userland/Libraries/LibSoftGPU/SoftwareRasterizer.h
+++ b/Userland/Libraries/LibSoftGPU/SoftwareRasterizer.h
@@ -50,6 +50,9 @@ struct RasterizerOptions {
     GLenum draw_buffer { GL_BACK };
     GLfloat depth_offset_factor { 0 };
     GLfloat depth_offset_constant { 0 };
+    bool enable_culling { false };
+    GLenum front_face { GL_CCW };
+    GLenum culled_sides { GL_BACK };
 };
 
 class SoftwareRasterizer final {