Renderer/Texture: Add Copy method (wip)

src/Nazara/OpenGLRenderer/OpenGLTexture.cpp

@@ -53,6 +53,32 @@ namespace Nz
 		m_texture.SetParameteri(GL_TEXTURE_SWIZZLE_A, format->swizzleA);
 	}
 
+	bool OpenGLTexture::Copy(const Texture& source, const Boxui& srcBox, const Vector3ui& dstPos)
+	{
+		const OpenGLTexture& glTexture = static_cast<const OpenGLTexture&>(source);
+
+		const GL::Context& context = m_texture.EnsureDeviceContext();
+
+		// Use glCopyImageSubData if available
+		if (context.glCopyImageSubData)
+		{
+			GLuint srcImage = glTexture.GetTexture().GetObjectId();
+			GLenum srcTarget = ToOpenGL(ToTextureTarget(glTexture.GetType()));
+
+			GLuint dstImage = m_texture.GetObjectId();
+			GLenum dstTarget = ToOpenGL(ToTextureTarget(m_params.type));
+
+			context.glCopyImageSubData(srcImage, srcTarget, 0, GLint(srcBox.x), GLint(srcBox.y), GLint(srcBox.z), dstImage, dstTarget, 0, GLint(dstPos.x), GLint(dstPos.y), GLint(dstPos.z), GLsizei(srcBox.width), GLsizei(srcBox.height), GLsizei(srcBox.depth));
+			return true;
+		}
+		else
+		{
+			//TODO: Blit using framebuffers
+		}
+
+		return false;
+	}
+
 	PixelFormat OpenGLTexture::GetFormat() const
 	{
 		return m_params.pixelFormat;