Conversion from ARGB to RGBA - c++

Question

I'm trying to write my own Color struct for a task I have.
My goal is that my buffer will always contain a RGBA value, even if it is initialized with ARGB values.
I have 2 constructors:
Takes R,G,B,A values of type uint8_t separately - Works like a charm.
Takes a uint32_t that holds an ARGB value - The problem begins here: I'm
I have a method that converts the provided ARGB into RGBA ("fromArgb").
Seems like only the conversion to the RGBA color Red works well, and all other color conversions are invalid.
Examples:
Color red = Color(0xFFFF0000); // Works well (Contains values:
Hex: #FF0000FF; R: 255, G: 0, B: 0, A: 255)
Color green = Color(0xFF008000); // Wrong - Actually Pinkish color
(Contains values: Hex: #008000FF R: 255, G: 0, B: 128, A: 0)
Color blue = Color(0xFF0000FF); // Wrong - Actually Yellowish color
(Contains values: Hex: #0000FFFF R: 255, G: 255, B: 0, A: 0)
Color yellow = Color(0xFFFFFF00); // Wrong - Actually Pinkish color
(Contains values: Hex: #FFFF00FF R: 255, G: 0, B: 255, A: 255)
I can't seem to find the problem.
I'll be more than glad to have some support from the community!
Example source Code:
struct Color
{
public:
/* Works fine!!! */
Color(uint8_t r, uint8_t g, uint8_t b, uint8_t a = 255)
{
buffer((r << 0) | (g << 8) | (b << 16) | (a << 24))
}
Color(const uint32_t argb)
{
buffer = fromArgb(argb);
}
inline uint32_t fromArgb(uint32_t argb)
{
return
// Source is in format: 0xAARRGGBB
((argb & 0x00FF0000) << 8) | //RR______
((argb & 0x0000FF00) << 8) | //__GG____
((argb & 0x000000FF) << 8) | //____BB__
((argb & 0xFF000000) >> 24); //______AA
// Return value is in format: 0xRRGGBBAA
}
inline uint8_t getRed(void) const
{
return (buffer >> 0) & 0xFF;
}
inline uint8_t getGreen(void) const
{
return (buffer >> 8) & 0xFF;
}
inline uint8_t getBlue(void) const
{
return (buffer >> 16) & 0xFF;
}
inline uint8_t getAlpha(void) const
{
return (buffer >> 24) & 0xFF;
}
/* Works fine!!!*/
std::string getHex(void) const
{
std::string result = "#";
char colorBuffer[255] = {};
// Order is intentionally end to beginning
sprintf_s(colorBuffer, 255, "%.2X", getAlpha());
result.append(colorBuffer);
sprintf_s(colorBuffer, 255, "%.2X", getBlue());
result.append(colorBuffer);
sprintf_s(colorBuffer, 255, "%.2X", getGreen());
result.append(colorBuffer);
sprintf_s(colorBuffer, 255, "%.2X", getRed());
result.append(colorBuffer);
return result;
}
private:
uint32_t buffer;
}

Answer 1

Looks to me that the class is holding an ABGR value, so obviously a conversion from ARGB to RGBA isn't helpful. This seems right (untested though).
inline uint32_t fromArgb(uint32_t argb)
{
return
// Source is in format: 0xAARRGGBB
((argb & 0x00FF0000) >> 16) | //______RR
((argb & 0x0000FF00)) | //____GG__
((argb & 0x000000FF) << 16) | /___BB____
((argb & 0xFF000000)); //AA______
// Return value is in format: 0xAABBGGRR
}