Merge remote-tracking branch 'origin/instanced-networks'

1 files changed, 36 insertions, 1 deletions

diff --git a/gfx/gl/shader.cpp b/gfx/gl/shader.cpp
index 5f83b83..0f75817 100644
--- a/gfx/gl/shader.cpp
+++ b/gfx/gl/shader.cpp
@@ -1,13 +1,48 @@
 #include "shader.h"
+#include <algorithm>
 #include <array>
 #include <stdexcept>
 #include <string>
 
+namespace {
+	auto
+	getInt(GLenum e)
+	{
+		GLint i {};
+		glGetIntegerv(e, &i);
+		return std::to_string(i);
+	}
+
+	using LookUpFunction = std::string (*)(GLenum);
+	constexpr std::array<std::tuple<std::string_view, GLenum, LookUpFunction>, 1> LOOKUPS {{
+			{"GL_MAX_GEOMETRY_OUTPUT_VERTICES", GL_MAX_GEOMETRY_OUTPUT_VERTICES, getInt},
+	}};
+}
+
 Shader::ShaderRef
 Shader::compile() const
 {
 	ShaderRef shader {type};
-	glShaderSource(shader, 1, &text, &len);
+	auto source = [&shader](auto text, GLint len) {
+		glShaderSource(shader, 1, &text, &len);
+	};
+	if (lookups) {
+		std::basic_string<GLchar> textMod {text};
+		for (const auto & match : ctre::range<R"(\bGL_[A-Z_]+\b)">(textMod)) {
+			if (const auto lookup = std::find_if(LOOKUPS.begin(), LOOKUPS.end(),
+						[&match](const auto & lookup) {
+							return std::get<std::string_view>(lookup) == match;
+						});
+					lookup != LOOKUPS.end()) {
+				const auto & [name, pname, getFunction] = *lookup;
+				textMod.replace(match.begin(), match.end(), getFunction(pname));
+			}
+		}
+		source(textMod.c_str(), static_cast<GLint>(textMod.length()));
+	}
+	else {
+		source(text.data(), static_cast<GLint>(text.length()));
+	}
 	glCompileShader(shader);
 
 	CheckShaderError(shader, GL_COMPILE_STATUS, false, "Error compiling shader!");