[ADD] Added BRRLIB_GetColor to convert RGBA values to an u32 color.

[CHG] Renamed GRRLIB_FBReadPixel to GRRLIB_GetPixelFromFB;
This commit is contained in:
Xane 2009-03-09 23:31:41 +00:00
parent b120658463
commit 1e934418d1
2 changed files with 28 additions and 14 deletions

View file

@ -1261,14 +1261,12 @@ bool GRRLIB_ScrShot(const char* File) {
* @param G2 A pointer to a variable receiving the second Green value.
* @param B2 A pointer to a variable receiving the second Blue value.
*/
void GRRLIB_FBReadPixel(int x, int y, u8 *R1, u8 *G1, u8 *B1, u8* R2, u8 *G2, u8 *B2 ) {
void GRRLIB_GetPixelFromFB(int x, int y, u8 *R1, u8 *G1, u8 *B1, u8* R2, u8 *G2, u8 *B2 ) {
// Position Correction
if (x > rmode->fbWidth) { x = rmode->fbWidth; }
if (x > (rmode->fbWidth/2)) { x = (rmode->fbWidth/2); }
if (x < 0) { x = 0; }
if (y > rmode->efbHeight) { y = rmode->efbHeight; }
if (y < 0) { y = 0; }
x = x / 2; /* FB is storing 2 pixels at once (YCbCr),
so we just need half of the width. */
// Preparing FB for reading
u32 Buffer = (((u32 *)xfb[fb])[y*(rmode->fbWidth/2)+x]);
@ -1280,22 +1278,23 @@ void GRRLIB_FBReadPixel(int x, int y, u8 *R1, u8 *G1, u8 *B1, u8* R2, u8 *G2, u8
Colors[2] = Y2
Colors[3] = Cr */
*R1 = GRRLIB_FBClamp( 1.164 * (Colors[0] - 16) + 1.596 * (Colors[3] - 128) );
*G1 = GRRLIB_FBClamp( 1.164 * (Colors[0] - 16) - 0.813 * (Colors[3] - 128) - 0.392 * (Colors[1] - 128) );
*B1 = GRRLIB_FBClamp( 1.164 * (Colors[0] - 16) + 2.017 * (Colors[1] - 128) );
*R1 = GRRLIB_ClampVar8( 1.164 * (Colors[0] - 16) + 1.596 * (Colors[3] - 128) );
*G1 = GRRLIB_ClampVar8( 1.164 * (Colors[0] - 16) - 0.813 * (Colors[3] - 128) - 0.392 * (Colors[1] - 128) );
*B1 = GRRLIB_ClampVar8( 1.164 * (Colors[0] - 16) + 2.017 * (Colors[1] - 128) );
*R2 = GRRLIB_FBClamp( 1.164 * (Colors[2] - 16) + 1.596 * (Colors[3] - 128) );
*G2 = GRRLIB_FBClamp( 1.164 * (Colors[2] - 16) - 0.813 * (Colors[3] - 128) - 0.392 * (Colors[1] - 128) );
*B2 = GRRLIB_FBClamp( 1.164 * (Colors[2] - 16) + 2.017 * (Colors[1] - 128) );
*R2 = GRRLIB_ClampVar8( 1.164 * (Colors[2] - 16) + 1.596 * (Colors[3] - 128) );
*G2 = GRRLIB_ClampVar8( 1.164 * (Colors[2] - 16) - 0.813 * (Colors[3] - 128) - 0.392 * (Colors[1] - 128) );
*B2 = GRRLIB_ClampVar8( 1.164 * (Colors[2] - 16) + 2.017 * (Colors[1] - 128) );
}
/**
* A helper function for the YCbCr -> RGB conversion.
* Clamps the given value into a range of 0 - 255 and thus preventing an overflow.
* @param The value to clamp.
* @param Value The value to clamp.
* @return Returns a clean, clamped unsigned char.
*/
u8 GRRLIB_FBClamp (float Value) {
u8 GRRLIB_ClampVar8(float Value) {
/* Using float to increase the precision.
This makes a full spectrum (0 - 255) possible. */
Value = roundf(Value);
@ -1306,3 +1305,15 @@ u8 GRRLIB_FBClamp (float Value) {
}
return (u8)Value;
}
/**
* Converts RGBA values to u32 color.
* @param r Amount of Red (0 - 255);
* @param g Amount of Green (0 - 255);
* @param b Amount of Blue (0 - 255);
* @param a Amount of Alpha (0 - 255);
* @return Returns the color in u32 format.
*/
u32 GRRLIB_GetColor( u8 r, u8 g, u8 b, u8 a ) {
return (r * 0x1000000) + (g * 0x10000) + (b * 0x100) + a;
}

View file

@ -157,8 +157,11 @@ void GRRLIB_Exit();
bool GRRLIB_ScrShot(const char*);
void GRRLIB_FBReadPixel(int x, int y, u8 *R1, u8 *G1, u8 *B1, u8* R2, u8 *G2, u8 *B2 );
u8 GRRLIB_FBClamp (float Value);
void GRRLIB_GetPixelFromFB(int x, int y, u8 *R1, u8 *G1, u8 *B1, u8* R2, u8 *G2, u8 *B2 );
u8 GRRLIB_ClampVar8 (float Value);
u32 GRRLIB_GetColor( u8 r, u8 g, u8 b, u8 a );
#ifdef __cplusplus
}