Bind texture units using GpuMaterial

src/material.cpp

@@ -0,0 +1,32 @@
+#include "material.h"
+#include "ShaderProgram.h"
+
+GpuMaterial::GpuMaterial(Material const &material)
+{
+    int texture_unit_counter = 0;
+
+    if (material.base_color_texture.has_value()) {
+        Binding binding{.uniform_name = "u_material.texture_diffuse",
+                        .texture_unit = texture_unit_counter++};
+        base_color_texture = std::make_pair(GpuImage(material.base_color_texture.value()), binding);
+    }
+
+    if (material.normal_map_texture.has_value()) {
+        Binding binding{.uniform_name = "u_material.texture_normal",
+                        .texture_unit = texture_unit_counter++};
+        normal_map_texture = std::make_pair(GpuImage(material.normal_map_texture.value()), binding);
+    }
+}
+void GpuMaterial::bind(ShaderProgram const &shader_program) const
+{
+    auto bind_texture = [&shader_program](auto const &texture) {
+        if (texture.has_value()) {
+            shader_program.setUniform(texture->second.uniform_name, texture->second.texture_unit);
+            glActiveTexture(GL_TEXTURE0 + texture->second.texture_unit);
+            glBindTexture(GL_TEXTURE_2D, texture->first.texture);
+        }
+    };
+
+    bind_texture(base_color_texture);
+    bind_texture(normal_map_texture);
+}