vtfpp: do not invalidate const guarantees

Author: craftablescience

include/vtfpp/VTF.h

@@ -407,7 +407,9 @@ class VTF {
 
 	[[nodiscard]] bool hasImageData() const;
 
-	[[nodiscard]] std::span<std::byte> getImageDataRaw(uint8_t mip = 0, uint16_t frame = 0, uint8_t face = 0, uint16_t slice = 0) const;
+	[[nodiscard]] std::span<const std::byte> getImageDataRaw(uint8_t mip = 0, uint16_t frame = 0, uint8_t face = 0, uint16_t slice = 0) const;
+
+	[[nodiscard]] std::span<std::byte> getImageDataRaw(uint8_t mip = 0, uint16_t frame = 0, uint8_t face = 0, uint16_t slice = 0);
 
 	[[nodiscard]] std::vector<std::byte> getImageDataAs(ImageFormat newFormat, uint8_t mip = 0, uint16_t frame = 0, uint8_t face = 0, uint16_t slice = 0) const;
 
@@ -423,7 +425,9 @@ class VTF {
 
 	[[nodiscard]] bool hasThumbnailData() const;
 
-	[[nodiscard]] std::span<std::byte> getThumbnailDataRaw() const;
+	[[nodiscard]] std::span<const std::byte> getThumbnailDataRaw() const;
+
+	[[nodiscard]] std::span<std::byte> getThumbnailDataRaw();
 
 	[[nodiscard]] std::vector<std::byte> getThumbnailDataAs(ImageFormat newFormat) const;
 
@@ -443,7 +447,9 @@ class VTF {
 
 	[[nodiscard]] bool hasFallbackData() const;
 
-	[[nodiscard]] std::span<std::byte> getFallbackDataRaw(uint8_t mip = 0, uint16_t frame = 0, uint8_t face = 0) const;
+	[[nodiscard]] std::span<const std::byte> getFallbackDataRaw(uint8_t mip = 0, uint16_t frame = 0, uint8_t face = 0) const;
+
+	[[nodiscard]] std::span<std::byte> getFallbackDataRaw(uint8_t mip = 0, uint16_t frame = 0, uint8_t face = 0);
 
 	[[nodiscard]] std::vector<std::byte> getFallbackDataAs(ImageFormat newFormat, uint8_t mip = 0, uint16_t frame = 0, uint8_t face = 0) const;
 

src/vtfpp/VTF.cpp

@@ -1927,7 +1927,16 @@ bool VTF::hasImageData() const {
 	return this->format != ImageFormat::EMPTY && this->width > 0 && this->height > 0;
 }
 
-std::span<std::byte> VTF::getImageDataRaw(uint8_t mip, uint16_t frame, uint8_t face, uint16_t slice) const {
+std::span<const std::byte> VTF::getImageDataRaw(uint8_t mip, uint16_t frame, uint8_t face, uint16_t slice) const {
+	if (const auto imageResource = this->getResource(Resource::TYPE_IMAGE_DATA)) {
+		if (uint32_t offset, length; ImageFormatDetails::getDataPosition(offset, length, this->format, mip, this->mipCount, frame, this->frameCount, face, this->getFaceCount(), this->width, this->height, slice, this->depth)) {
+			return imageResource->data.subspan(offset, length);
+		}
+	}
+	return {};
+}
+
+std::span<std::byte> VTF::getImageDataRaw(uint8_t mip, uint16_t frame, uint8_t face, uint16_t slice) {
 	if (const auto imageResource = this->getResource(Resource::TYPE_IMAGE_DATA)) {
 		if (uint32_t offset, length; ImageFormatDetails::getDataPosition(offset, length, this->format, mip, this->mipCount, frame, this->frameCount, face, this->getFaceCount(), this->width, this->height, slice, this->depth)) {
 			return imageResource->data.subspan(offset, length);
@@ -2057,7 +2066,14 @@ bool VTF::hasThumbnailData() const {
 	return this->thumbnailFormat != ImageFormat::EMPTY && this->thumbnailWidth > 0 && this->thumbnailHeight > 0;
 }
 
-std::span<std::byte> VTF::getThumbnailDataRaw() const {
+std::span<const std::byte> VTF::getThumbnailDataRaw() const {
+	if (const auto thumbnailResource = this->getResource(Resource::TYPE_THUMBNAIL_DATA)) {
+		return thumbnailResource->data;
+	}
+	return {};
+}
+
+std::span<std::byte> VTF::getThumbnailDataRaw() {
 	if (const auto thumbnailResource = this->getResource(Resource::TYPE_THUMBNAIL_DATA)) {
 		return thumbnailResource->data;
 	}
@@ -2153,7 +2169,16 @@ bool VTF::hasFallbackData() const {
 	return this->fallbackWidth > 0 && this->fallbackHeight > 0 && this->fallbackMipCount > 0;
 }
 
-std::span<std::byte> VTF::getFallbackDataRaw(uint8_t mip, uint16_t frame, uint8_t face) const {
+std::span<const std::byte> VTF::getFallbackDataRaw(uint8_t mip, uint16_t frame, uint8_t face) const {
+	if (const auto fallbackResource = this->getResource(Resource::TYPE_FALLBACK_DATA)) {
+		if (uint32_t offset, length; ImageFormatDetails::getDataPosition(offset, length, this->format, mip, this->fallbackMipCount, frame, this->frameCount, face, this->getFaceCount(), this->fallbackWidth, this->fallbackHeight)) {
+			return fallbackResource->data.subspan(offset, length);
+		}
+	}
+	return {};
+}
+
+std::span<std::byte> VTF::getFallbackDataRaw(uint8_t mip, uint16_t frame, uint8_t face) {
 	if (const auto fallbackResource = this->getResource(Resource::TYPE_FALLBACK_DATA)) {
 		if (uint32_t offset, length; ImageFormatDetails::getDataPosition(offset, length, this->format, mip, this->fallbackMipCount, frame, this->frameCount, face, this->getFaceCount(), this->fallbackWidth, this->fallbackHeight)) {
 			return fallbackResource->data.subspan(offset, length);