make BC4 channel readonly

quicktex/s3tc/bc3/BC3Decoder.cpp

@@ -29,6 +29,6 @@ namespace quicktex::s3tc  {
 
 void BC3Decoder::DecodeBlock(Color4x4 dest, BC3Block *const block) const noexcept(ndebug) {
     _bc1_decoder->DecodeBlock(dest, &(block->color_block), false);
-    _bc4_decoder->DecodeBlock(dest, &(block->alpha_block), 3);
+    _bc4_decoder->DecodeBlock(dest, &(block->alpha_block));
 }
 }  // namespace quicktex::s3tc

quicktex/s3tc/bc3/BC3Encoder.cpp

@@ -22,9 +22,9 @@
 #include "../../BlockView.h"
 #include "BC3Block.h"
 
-namespace quicktex::s3tc  {
+namespace quicktex::s3tc {
 void BC3Encoder::EncodeBlock(Color4x4 pixels, BC3Block *dest) const {
     _bc1_encoder->EncodeBlock(pixels, &(dest->color_block));
-    _bc4_encoder->EncodeBlock(pixels, &(dest->alpha_block), 3);
+    _bc4_encoder->EncodeBlock(pixels, &(dest->alpha_block));
 }
 }  // namespace quicktex::s3tc

quicktex/s3tc/bc4/BC4Decoder.h

@@ -28,20 +28,19 @@
 #include "../../ndebug.h"
 #include "BC4Block.h"
 
-namespace quicktex::s3tc  {
+namespace quicktex::s3tc {
+
 class BC4Decoder : public BlockDecoderTemplate<BC4Block, 4, 4> {
    public:
-    BC4Decoder(uint8_t channel = 3) { SetChannel(channel); }
+    BC4Decoder(uint8_t channel = 3) {
+        if (channel >= 4U) throw std::invalid_argument("Channel out of range");
+        _channel = channel;
+    }
 
     void DecodeBlock(Color4x4 dest, BC4Block *const block) const noexcept(ndebug) override { DecodeBlock(dest.GetChannel(_channel), block); }
-    void DecodeBlock(Color4x4 dest, BC4Block *const block, uint8_t channel) const noexcept(ndebug) { DecodeBlock(dest.GetChannel(channel), block); }
     void DecodeBlock(Byte4x4 dest, BC4Block *const block) const noexcept(ndebug);
 
     uint8_t GetChannel() const { return _channel; }
-    void SetChannel(uint8_t channel) {
-        if (channel >= 4U) throw std::invalid_argument("Channel out of range");
-        _channel = channel;
-    }
 
    private:
     uint8_t _channel;

quicktex/s3tc/bc4/BC4Encoder.h

@@ -28,21 +28,19 @@
 #include "../../ndebug.h"
 #include "BC4Block.h"
 
-namespace quicktex::s3tc  {
+namespace quicktex::s3tc {
 
 class BC4Encoder : public BlockEncoderTemplate<BC4Block, 4, 4> {
    public:
-    BC4Encoder(const uint8_t channel) { SetChannel(channel); }
+    BC4Encoder(const uint8_t channel) {
+        if (channel >= 4) throw std::invalid_argument("Channel out of range");
+        _channel = channel;
+    }
 
     void EncodeBlock(Color4x4 pixels, BC4Block *const dest) const override { EncodeBlock(pixels.GetChannel(_channel), dest); }
-    void EncodeBlock(Color4x4 pixels, BC4Block *const dest, uint8_t channel) const noexcept(ndebug) { EncodeBlock(pixels.GetChannel(channel), dest); }
     void EncodeBlock(Byte4x4 pixels, BC4Block *const dest) const noexcept(ndebug);
 
     uint8_t GetChannel() const { return _channel; }
-    void SetChannel(uint8_t channel) {
-        if (channel >= 4) throw std::invalid_argument("Channel out of range");
-        _channel = channel;
-    }
 
    private:
     uint8_t _channel;

quicktex/s3tc/bc4/_bindings.cpp

@@ -45,13 +45,13 @@ void InitBC4(py::module_ &s3tc) {
     py::class_<BC4Encoder> bc4_encoder(bc4, "BC4Encoder", block_encoder);
 
     bc4_encoder.def(py::init<uint8_t>(), py::arg("channel") = 3);
-    bc4_encoder.def_property("channel", &BC4Encoder::GetChannel, &BC4Encoder::SetChannel);
+    bc4_encoder.def_property_readonly("channel", &BC4Encoder::GetChannel, "The channel to read from. 0 to 3 inclusive. Readonly.");
 
     // BC4Decoder
     py::class_<BC4Decoder> bc4_decoder(bc4, "BC4Decoder", block_decoder);
 
     bc4_decoder.def(py::init<uint8_t>(), py::arg("channel") = 3);
-    bc4_decoder.def_property("channel", &BC4Decoder::GetChannel, &BC4Decoder::SetChannel);
+    bc4_decoder.def_property_readonly("channel", &BC4Decoder::GetChannel, "The channel to write to. 0 to 3 inclusive. Readonly.");
 }
 
 }  // namespace quicktex::bindings