LibGL: Make texture coordinates a FloatVector4

In OpenGL, texture coordinates can have up to 4 values. This change
will help with easy application of texture coordinate matrix
transformations in the future.

Additionally, correct the initial value for texture coordinates to
`{ 0.f, 0.f, 0.f, 1.f}`.

Userland/Libraries/LibGL/GLStruct.h

@@ -20,7 +20,7 @@ struct GLColor {
 struct GLVertex {
     FloatVector4 position;
     FloatVector4 color;
-    FloatVector2 tex_coord;
+    FloatVector4 tex_coord;
     FloatVector3 normal;
 };
 

Userland/Libraries/LibGL/SoftwareGLContext.cpp

@@ -608,7 +608,7 @@ void SoftwareGLContext::gl_vertex(GLdouble x, GLdouble y, GLdouble z, GLdouble w
 
     vertex.position = { static_cast<float>(x), static_cast<float>(y), static_cast<float>(z), static_cast<float>(w) };
     vertex.color = m_current_vertex_color;
-    vertex.tex_coord = { m_current_vertex_tex_coord.x(), m_current_vertex_tex_coord.y() };
+    vertex.tex_coord = m_current_vertex_tex_coord;
     vertex.normal = m_current_vertex_normal;
 
     vertex_list.append(vertex);

Userland/Libraries/LibGL/SoftwareGLContext.h

@@ -171,7 +171,7 @@ private:
     GLint m_clear_stencil { 0 };
 
     FloatVector4 m_current_vertex_color = { 1.0f, 1.0f, 1.0f, 1.0f };
-    FloatVector4 m_current_vertex_tex_coord = { 0.0f, 0.0f, 0.0f, 0.0f };
+    FloatVector4 m_current_vertex_tex_coord = { 0.0f, 0.0f, 0.0f, 1.0f };
     FloatVector3 m_current_vertex_normal = { 0.0f, 0.0f, 1.0f };
 
     Vector<GLVertex, 96> vertex_list;

Userland/Libraries/LibGL/SoftwareRasterizer.cpp

@@ -496,7 +496,7 @@ SoftwareRasterizer::SoftwareRasterizer(const Gfx::IntSize& min_size)
 
 void SoftwareRasterizer::submit_triangle(GLTriangle const& triangle, TextureUnit::BoundList const& bound_texture_units)
 {
-    rasterize_triangle(m_options, *m_render_target, *m_depth_buffer, triangle, [this, &bound_texture_units](const FloatVector2& uv, const FloatVector4& color, float z) -> FloatVector4 {
+    rasterize_triangle(m_options, *m_render_target, *m_depth_buffer, triangle, [this, &bound_texture_units](FloatVector4 const& uv, FloatVector4 const& color, float z) -> FloatVector4 {
         FloatVector4 fragment = color;
 
         for (auto const& texture_unit : bound_texture_units) {

Userland/Libraries/LibGL/Tex/Sampler2D.cpp

@@ -50,7 +50,7 @@ static constexpr float wrap(float value, GLint mode, int num_texels)
     }
 }
 
-FloatVector4 Sampler2D::sample(FloatVector2 const& uv) const
+FloatVector4 Sampler2D::sample(FloatVector4 const& uv) const
 {
     // FIXME: Calculate the correct mipmap level here, need to receive uv derivatives for that
     unsigned lod = 0;

Userland/Libraries/LibGL/Tex/Sampler2D.h

@@ -31,7 +31,7 @@ public:
     void set_wrap_s_mode(GLint value) { m_wrap_s_mode = value; }
     void set_wrap_t_mode(GLint value) { m_wrap_t_mode = value; }
 
-    FloatVector4 sample(FloatVector2 const& uv) const;
+    FloatVector4 sample(FloatVector4 const& uv) const;
 
 private:
     Texture2D const& m_texture;