[core] Introduce gl::Program template

1 files changed, 31 insertions, 0 deletions

diff --git a/src/mbgl/programs/program.hpp b/src/mbgl/programs/program.hpp
new file mode 100644
index 0000000000..9f154b051a
--- /dev/null
+++ b/src/mbgl/programs/program.hpp
@@ -0,0 +1,31 @@
+#pragma once
+
+#include <mbgl/gl/program.hpp>
+
+#include <cassert>
+
+namespace mbgl {
+
+enum class ProgramDefines : bool {
+    None = false,
+    Overdraw = true,
+};
+
+template <class Shaders, class As, class Us>
+class Program : public gl::Program<As, Us> {
+public:
+    Program(gl::Context& context, ProgramDefines defines)
+        : gl::Program<As, Us>(context, Shaders::vertexSource, fragmentSource(defines))
+        {}
+
+    static std::string fragmentSource(ProgramDefines defines) {
+        std::string fragment = Shaders::fragmentSource;
+        if (defines == ProgramDefines::Overdraw) {
+            assert(fragment.find("#ifdef OVERDRAW_INSPECTOR") != std::string::npos);
+            fragment.replace(fragment.find_first_of('\n'), 1, "\n#define OVERDRAW_INSPECTOR\n");
+        }
+        return fragment;
+    }
+};
+
+} // namespace mbgl