From f1f076acf4702363d780075c0d92279cb417fa7b Mon Sep 17 00:00:00 2001
From: Robert <robert.trololo@gmail.com>
Date: Thu, 21 Jan 2021 16:27:41 +0100
Subject: [PATCH] Improved Binding of textures

---
 examples/debug/main.cpp |  6 ++----
 include/shader.hpp      |  3 +++
 include/texture.hpp     | 10 ++++++++++
 src/shader.cpp          |  6 ++++++
 src/texture.cpp         |  6 ++++++
 5 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/examples/debug/main.cpp b/examples/debug/main.cpp
index 97f6f6c..3fefb4d 100644
--- a/examples/debug/main.cpp
+++ b/examples/debug/main.cpp
@@ -86,10 +86,8 @@ int main(int argc, char** argv)
 
 		oglu::ClearScreen(GL_COLOR_BUFFER_BIT, oglu::Color(0.29f, 0.13f, 0.23f));
 
-		oglu::ActiveTexture(0);
-		crate->Bind();
-		oglu::ActiveTexture(1);
-		opengl->Bind();
+		crate->BindAs(0);
+		opengl->BindAs(1);
 
 		shader->Use();
 		shader->SetUniform("texture1", 0);
diff --git a/include/shader.hpp b/include/shader.hpp
index 2e84cdb..d458f9e 100644
--- a/include/shader.hpp
+++ b/include/shader.hpp
@@ -14,6 +14,9 @@
 namespace oglu
 {
 	class Color;
+	class AbstractTexture;
+
+	typedef std::shared_ptr<AbstractTexture> Texture;
 
 	/**
 	 * @brief An object representing an OpenGL Shader Program.
diff --git a/include/texture.hpp b/include/texture.hpp
index 4806b97..31afb5e 100644
--- a/include/texture.hpp
+++ b/include/texture.hpp
@@ -59,6 +59,16 @@ namespace oglu
 		 */
 		void Bind();
 
+		/**
+		 * @brief Sets active texture and binds this texture.
+		 * 
+		 * In order to use multiple textures in the same shader the active texture unit needs to be specified.
+		 * This function first sets the active texture unit and then binds the texture.
+		 * 
+		 * @param[in] index Index of the texture unit (Note: This index is actually an offset to @p GL_TEXTURE0)
+		 */
+		void BindAs(GLbyte index);
+
 		/**
 		 * @brief Unbind this texture.
 		 */
diff --git a/src/shader.cpp b/src/shader.cpp
index edc4567..f3edb4d 100644
--- a/src/shader.cpp
+++ b/src/shader.cpp
@@ -40,6 +40,7 @@ namespace oglu
 			glGetShaderInfoLog(vertexShader, 512, NULL, infoLog);
 			std::string err = ("Failed to compile shader " + std::string(vertexShaderFile) + "\n" + infoLog);
 			delete source;
+			glDeleteShader(vertexShader);
 			throw std::runtime_error(err);
 		}
 		delete source;
@@ -57,6 +58,8 @@ namespace oglu
 			glGetShaderInfoLog(fragmentShader, 512, NULL, infoLog);
 			std::string err = ("Failed to compile shader " + std::string(fragmentShaderFile) + "\n" + infoLog);
 			delete source;
+			glDeleteShader(vertexShader);
+			glDeleteShader(fragmentShader);
 			throw std::runtime_error(err);
 		}
 		delete source;
@@ -72,6 +75,9 @@ namespace oglu
 		{
 			glGetProgramInfoLog(program, 512, NULL, infoLog);
 			std::string err = ("Failed to link program.\n" + std::string(infoLog));
+			glDeleteShader(vertexShader);
+			glDeleteShader(fragmentShader);
+			glDeleteProgram(program);
 			throw std::runtime_error(err);
 		}
 
diff --git a/src/texture.cpp b/src/texture.cpp
index aa550e1..0948bba 100644
--- a/src/texture.cpp
+++ b/src/texture.cpp
@@ -68,6 +68,12 @@ namespace oglu
 		glBindTexture(GL_TEXTURE_2D, texture);
 	}
 
+	void AbstractTexture::BindAs(GLbyte index)
+	{
+		glActiveTexture(GL_TEXTURE0 + index);
+		glBindTexture(GL_TEXTURE_2D, texture);
+	}
+
 	void AbstractTexture::Unbind()
 	{
 		glBindTexture(GL_TEXTURE_2D, 0);