Wrong Colours in GU_PSM_5551 colour mode

[Mr.Modem]

I started playing around with libGU a couple of days ago. I thought I'd start with something easy and looked at the Line Sample. I took away all the unnecessary code til I just had a function to draw lines. It worked perfectly. Then I switched to 5551 colour mode and wrote a simple function to convert 8888 colours to 5551 colours. The function still draws lines but they are in wrong colour, blue becomes green and green becomes orange. I searched the forum and found an other colour conversion function, but it gave me the same result. I printed out the coulor on the screen to check that it was the right value. So can someone tell me what the hell I do wrong!

Code: Select all

#include <pspkernel.h>
#include <pspdisplay.h>
#include <pspdebug.h>
#include <pspctrl.h>
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <string.h>
#include <time.h>

#include <pspgu.h>

PSP_MODULE_INFO&#40;"Line Test", 0, 1, 1&#41;;
PSP_MAIN_THREAD_ATTR&#40;THREAD_ATTR_USER&#41;;
#define printf pspDebugScreenPrintf

static unsigned int __attribute__&#40;&#40;aligned&#40;16&#41;&#41;&#41; list&#91;262144&#93;;

struct Vertex
&#123;
	float x,y,z;
&#125;;

int SetupCallbacks&#40;&#41;;

int done = 0;

#define BUF_WIDTH &#40;512&#41;
#define SCR_WIDTH &#40;480&#41;
#define SCR_HEIGHT &#40;272&#41;
#define PIXEL_SIZE &#40;2&#41;
#define FRAME_SIZE &#40;BUF_WIDTH * SCR_HEIGHT * PIXEL_SIZE&#41;
#define ZBUF_SIZE &#40;BUF_WIDTH SCR_HEIGHT * 2&#41; /* zbuffer seems to be 16-bit? */

void DrawLine&#40;int x1, int y1, int x2, int y2&#41;;
void InitGFX&#40;&#41;;
void Render&#40;&#41;;

void DrawLine&#40;int x1, int y1, int x2, int y2&#41;
&#123;
	unsigned char r=255,b=0,g=0;
	unsigned short Color;
    Color=&#40;&#40;b>>3&#41;<<10&#41; | &#40;&#40;g>>3&#41;<<5&#41; | &#40;r>>3&#41; | 0x8000;
		sceGuColor&#40;Color&#41;;
			struct Vertex* vertices = sceGuGetMemory&#40;&#40;2&#41; * sizeof&#40;struct Vertex&#41;&#41;;

			vertices&#91;0&#93;.x = x1;
			vertices&#91;0&#93;.y = y1;
			vertices&#91;1&#93;.x = x2;
			vertices&#91;1&#93;.y = y2;
		
			sceGuDrawArray&#40;GU_LINE_STRIP,GU_VERTEX_32BITF|GU_TRANSFORM_2D,&#40;2&#41;,0,vertices&#41;;
&#125;

void InitGFX&#40;&#41;
&#123;

	sceGuInit&#40;&#41;;

	sceGuStart&#40;GU_DIRECT,list&#41;;
	sceGuDrawBuffer&#40;GU_PSM_5551,&#40;void*&#41;0,BUF_WIDTH&#41;;
	sceGuDispBuffer&#40;SCR_WIDTH,SCR_HEIGHT,&#40;void*&#41;FRAME_SIZE,BUF_WIDTH&#41;;
	sceGuDepthBuffer&#40;&#40;void*&#41;&#40;FRAME_SIZE*2&#41;,BUF_WIDTH&#41;;
	sceGuOffset&#40;2048 - &#40;SCR_WIDTH/2&#41;,2048 - &#40;SCR_HEIGHT/2&#41;&#41;;
	sceGuViewport&#40;2048,2048,SCR_WIDTH,SCR_HEIGHT&#41;;
	sceGuDepthRange&#40;0xc350,0x2710&#41;;
	sceGuScissor&#40;0,0,SCR_WIDTH,SCR_HEIGHT&#41;;
	sceGuEnable&#40;GU_SCISSOR_TEST&#41;;
	sceGuFinish&#40;&#41;;
	sceGuSync&#40;0,0&#41;;

	sceDisplayWaitVblankStart&#40;&#41;;
	sceGuDisplay&#40;GU_TRUE&#41;;
&#125;


void Render&#40;&#41;
&#123;
		sceGuStart&#40;GU_DIRECT,list&#41;;

		// clear screen

		sceGuClearColor&#40;0&#41;;
		sceGuClear&#40;GU_COLOR_BUFFER_BIT&#41;;
		DrawLine&#40;0,0,240,272&#41;;
		// wait for next frame

		sceGuFinish&#40;&#41;;
		sceGuSync&#40;0,0&#41;;
		sceDisplayWaitVblankStart&#40;&#41;;
		sceGuSwapBuffers&#40;&#41;;
&#125;


int main&#40;int argc, char* argv&#91;&#93;&#41;
&#123;

	SetupCallbacks&#40;&#41;;
	pspDebugScreenInit&#40;&#41;;
	InitGFX&#40;&#41;;
	while&#40;!done&#41;
	&#123;
	Render&#40;&#41;;
	&#125;

	sceGuTerm&#40;&#41;;

	sceKernelExitGame&#40;&#41;;
	return 0;
&#125;

[memon]

Unless you are dealing with vertex attributes or pixels, the API assumes R8G8B8A8 format. So you can change the frame buffer format but leave your data as it was.

[Mr.Modem]

Thanks it worked!