From 11fea6b597959fa8c66cb715cf67bef39aca573e Mon Sep 17 00:00:00 2001
From: Jelle Raaijmakers <jelle@gmta.nl>
Date: Wed, 1 Dec 2021 14:34:26 +0100
Subject: [PATCH] LibGL: Implement `glListBase`

---
 Userland/Libraries/LibGL/GL/gl.h               |  1 +
 Userland/Libraries/LibGL/GLContext.h           |  1 +
 Userland/Libraries/LibGL/GLLists.cpp           |  5 +++++
 Userland/Libraries/LibGL/SoftwareGLContext.cpp | 11 ++++++++++-
 Userland/Libraries/LibGL/SoftwareGLContext.h   |  2 ++
 5 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/Userland/Libraries/LibGL/GL/gl.h b/Userland/Libraries/LibGL/GL/gl.h
index 79aeb5be76..2be8dc296c 100644
--- a/Userland/Libraries/LibGL/GL/gl.h
+++ b/Userland/Libraries/LibGL/GL/gl.h
@@ -393,6 +393,7 @@ GLAPI GLuint glGenLists(GLsizei range);
 GLAPI void glCallList(GLuint list);
 GLAPI void glCallLists(GLsizei n, GLenum type, void const* lists);
 GLAPI void glDeleteLists(GLuint list, GLsizei range);
+GLAPI void glListBase(GLuint base);
 GLAPI void glEndList(void);
 GLAPI void glNewList(GLuint list, GLenum mode);
 GLAPI void glFlush();
diff --git a/Userland/Libraries/LibGL/GLContext.h b/Userland/Libraries/LibGL/GLContext.h
index ba170a2cae..c7590cdc2d 100644
--- a/Userland/Libraries/LibGL/GLContext.h
+++ b/Userland/Libraries/LibGL/GLContext.h
@@ -50,6 +50,7 @@ public:
     virtual void gl_call_list(GLuint list) = 0;
     virtual void gl_call_lists(GLsizei n, GLenum type, void const* lists) = 0;
     virtual void gl_delete_lists(GLuint list, GLsizei range) = 0;
+    virtual void gl_list_base(GLuint base) = 0;
     virtual void gl_end_list(void) = 0;
     virtual void gl_new_list(GLuint list, GLenum mode) = 0;
     virtual void gl_flush() = 0;
diff --git a/Userland/Libraries/LibGL/GLLists.cpp b/Userland/Libraries/LibGL/GLLists.cpp
index bf6fe17bdf..e1b34ec691 100644
--- a/Userland/Libraries/LibGL/GLLists.cpp
+++ b/Userland/Libraries/LibGL/GLLists.cpp
@@ -29,6 +29,11 @@ void glDeleteLists(GLuint list, GLsizei range)
     return g_gl_context->gl_delete_lists(list, range);
 }
 
+void glListBase(GLuint base)
+{
+    return g_gl_context->gl_list_base(base);
+}
+
 void glEndList(void)
 {
     return g_gl_context->gl_end_list();
diff --git a/Userland/Libraries/LibGL/SoftwareGLContext.cpp b/Userland/Libraries/LibGL/SoftwareGLContext.cpp
index 323850811e..efb526cf1e 100644
--- a/Userland/Libraries/LibGL/SoftwareGLContext.cpp
+++ b/Userland/Libraries/LibGL/SoftwareGLContext.cpp
@@ -926,7 +926,7 @@ void SoftwareGLContext::gl_call_lists(GLsizei n, GLenum type, void const* lists)
     auto invoke_all_lists = [&]<typename T>(T const* lists) {
         for (int i = 0; i < n; ++i) {
             auto list = static_cast<size_t>(lists[i]);
-            invoke_list(list);
+            invoke_list(m_list_base + list);
         }
     };
     switch (type) {
@@ -970,6 +970,15 @@ void SoftwareGLContext::gl_delete_lists(GLuint list, GLsizei range)
         entry.entries.clear_with_capacity();
 }
 
+void SoftwareGLContext::gl_list_base(GLuint base)
+{
+    APPEND_TO_CALL_LIST_AND_RETURN_IF_NEEDED(gl_list_base, base);
+
+    RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
+
+    m_list_base = base;
+}
+
 void SoftwareGLContext::gl_end_list()
 {
     RETURN_WITH_ERROR_IF(m_in_draw_state, GL_INVALID_OPERATION);
diff --git a/Userland/Libraries/LibGL/SoftwareGLContext.h b/Userland/Libraries/LibGL/SoftwareGLContext.h
index c99c3fe91a..6bc51700b3 100644
--- a/Userland/Libraries/LibGL/SoftwareGLContext.h
+++ b/Userland/Libraries/LibGL/SoftwareGLContext.h
@@ -61,6 +61,7 @@ public:
     virtual void gl_call_list(GLuint list) override;
     virtual void gl_call_lists(GLsizei n, GLenum type, void const* lists) override;
     virtual void gl_delete_lists(GLuint list, GLsizei range) override;
+    virtual void gl_list_base(GLuint base) override;
     virtual void gl_end_list(void) override;
     virtual void gl_new_list(GLuint list, GLenum mode) override;
     virtual void gl_flush() override;
@@ -254,6 +255,7 @@ private:
     static constexpr size_t max_allowed_gl_call_depth { 128 };
     size_t m_gl_call_depth { 0 };
     Vector<Listing> m_listings;
+    size_t m_list_base { 0 };
     struct CurrentListing {
         Listing listing;
         size_t index { 0 };