OpenGL: Added method OpenGLContext::setTextureMagnificationFilter to change GL's texture magnification filter

modules/juce_opengl/opengl/juce_OpenGLContext.cpp

@@ -836,6 +836,11 @@ void OpenGLContext::setPixelFormat (const OpenGLPixelFormat& preferredPixelForma
     openGLPixelFormat = preferredPixelFormat;
 }
 
+void OpenGLContext::setTextureMagnificationFilter (OpenGLContext::TextureMagnificationFilter magFilterMode) noexcept
+{
+    texMagFilter = magFilterMode;
+}
+
 void OpenGLContext::setNativeSharedContext (void* nativeContextToShareWith) noexcept
 {
     // This method must not be called when the context has already been attached!

modules/juce_opengl/opengl/juce_OpenGLContext.h

@@ -27,6 +27,8 @@
 namespace juce
 {
 
+class OpenGLTexture;
+
 //==============================================================================
 /**
     Creates an OpenGL context, which can be attached to a component.
@@ -97,6 +99,20 @@ public:
     */
     void setPixelFormat (const OpenGLPixelFormat& preferredPixelFormat) noexcept;
 
+    /** Texture magnification filters, used by setTextureMagnificationFilter(). */
+    enum TextureMagnificationFilter
+    {
+        nearest,
+        linear
+    };
+
+    /** Sets the texture magnification filter. By default the texture magnification
+        filter is linear. However, for faster rendering you may want to use the
+        'nearest' magnification filter. This option will not affect any textures
+        created before this function was called. */
+    void setTextureMagnificationFilter (TextureMagnificationFilter magFilterMode) noexcept;
+
+     //==============================================================================
     /** Provides a context with which you'd like this context's resources to be shared.
         The object passed-in here is a platform-dependent native context object, and
         must not be deleted while this context may still be using it! To turn off sharing,
@@ -298,6 +314,8 @@ public:
    #endif
 
 private:
+    friend class OpenGLTexture;
+
     class CachedImage;
     class Attachment;
     NativeContext* nativeContext = nullptr;
@@ -309,6 +327,7 @@ private:
     OpenGLVersion versionRequired = defaultGLVersion;
     size_t imageCacheMaxSize = 8 * 1024 * 1024;
     bool renderComponents = true, useMultisampling = false, continuousRepaint = false, overrideCanAttach = false;
+    TextureMagnificationFilter texMagFilter = linear;
 
     //==============================================================================
     struct AsyncWorker  : public ReferenceCountedObject

modules/juce_opengl/opengl/juce_OpenGLTexture.cpp

@@ -65,7 +65,9 @@ void OpenGLTexture::create (const int w, const int h, const void* pixels, GLenum
         glGenTextures (1, &textureID);
         glBindTexture (GL_TEXTURE_2D, textureID);
         glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
-        glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+        auto glMagFilter = (ownerContext->texMagFilter == OpenGLContext::linear ? GL_LINEAR : GL_NEAREST);
+        glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, glMagFilter);
         glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
         glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
         JUCE_CHECK_OPENGL_ERROR