shithub: tinygl

ref: 3b961717be648d0810bb364e3cacbd4be8f7ce0b
dir: /src/zbuffer.c/

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/*

 * Z buffer: 16 bits Z / 16 bits color
 * 
 */
#include <stdlib.h>
#include <stdio.h>
#include <assert.h>
#include <string.h>
//#include "../include/GL/gl.h"
#include "../include/zbuffer.h"

ZBuffer *ZB_open(GLint xsize, GLint ysize, GLint mode,
		 GLint nb_colors,
		 GLubyte *color_indexes,
		 GLint *color_table,
		 void *frame_buffer)
{
    ZBuffer *zb;
    GLint size;

    zb = gl_malloc(sizeof(ZBuffer));
    if (zb == NULL)
	return NULL;

    zb->xsize = xsize;
    zb->ysize = ysize;
    zb->mode = mode;
    zb->linesize = (xsize * PSZB + 3) & ~3;

    switch (mode) {
#ifdef TGL_FEATURE_8_BITS
    case ZB_MODE_INDEX:
	ZB_initDither(zb, nb_colors, color_indexes, color_table);
	break;
#endif
#ifdef TGL_FEATURE_32_BITS
    case ZB_MODE_RGBA:
#endif
#ifdef TGL_FEATURE_24_BITS
    case ZB_MODE_RGB24:
#endif
    case ZB_MODE_5R6G5B:
	zb->nb_colors = 0;
	break;
    default:
	goto error;
    }

    size = zb->xsize * zb->ysize * sizeof(unsigned short);

    zb->zbuf = gl_malloc(size);
    if (zb->zbuf == NULL)
	goto error;

    if (frame_buffer == NULL) {
	zb->pbuf = gl_malloc(zb->ysize * zb->linesize);
	if (zb->pbuf == NULL) {
	    gl_free(zb->zbuf);
	    goto error;
	}
	zb->frame_buffer_allocated = 1;
    } else {
	zb->frame_buffer_allocated = 0;
	zb->pbuf = frame_buffer;
    }

    zb->current_texture = NULL;

    return zb;
  error:
    gl_free(zb);
    return NULL;
}

void ZB_close(ZBuffer * zb)
{
#ifdef TGL_FEATURE_8_BITS
    if (zb->mode == ZB_MODE_INDEX)
	ZB_closeDither(zb);
#endif

    if (zb->frame_buffer_allocated)
	gl_free(zb->pbuf);

    gl_free(zb->zbuf);
    gl_free(zb);
}

void ZB_resize(ZBuffer * zb, void *frame_buffer, GLint xsize, GLint ysize)
{
    GLint size;

    /* xsize must be a multiple of 4 */
    xsize = xsize & ~3;

    zb->xsize = xsize;
    zb->ysize = ysize;
    zb->linesize = (xsize * PSZB + 3) & ~3;

    size = zb->xsize * zb->ysize * sizeof(unsigned short);

    gl_free(zb->zbuf);
    zb->zbuf = gl_malloc(size);

    if (zb->frame_buffer_allocated)
	gl_free(zb->pbuf);

    if (frame_buffer == NULL) {
	zb->pbuf = gl_malloc(zb->ysize * zb->linesize);
	zb->frame_buffer_allocated = 1;
    } else {
	zb->pbuf = frame_buffer;
	zb->frame_buffer_allocated = 0;
    }
}


#if TGL_FEATURE_32_BITS == 1
inline PIXEL pxReverse32(PIXEL x)
{

    return
    // Source is in format: 0xAARRGGBB
        ((x & 0xFF000000) >> 24) | //______AA
        ((x & 0x00FF0000) >>  8) | //____RR__
        ((x & 0x0000FF00) <<  8) | //__GG____
        ((x & 0x000000FF) << 24);  //BB______
    // Return value is in format:  0xBBGGRRAA
}
#endif


static void ZB_copyBuffer(ZBuffer * zb,
                          void *buf,
                          GLint linesize)
{
    GLubyte *p1;
    PIXEL *q;
    GLint y;
    #if !TGL_FEATURE_NO_COPY_COLOR
    GLint n;
    #endif

    q = zb->pbuf;
    p1 = buf;
    #if !TGL_FEATURE_NO_COPY_COLOR
    n = zb->xsize * PSZB;
    #endif
    for (y = 0; y < zb->ysize; y++) {
    #if TGL_FEATURE_NO_COPY_COLOR
		for(GLint i = 0; i < zb->xsize; i++)
		{
			if((*(q+i) & TGL_COLOR_MASK) != TGL_NO_COPY_COLOR)
				*(((PIXEL*)p1) + i) = *(q+i);
		}
    #else
		memcpy(p1, q, n);
	#endif
	p1 += linesize; //TODO make this a predictable behavior.
	q = (PIXEL *) ((GLbyte *) q + zb->linesize);
    }
}

#if TGL_FEATURE_RENDER_BITS == 16

/* 32 bpp copy */
/*

#ifdef TGL_FEATURE_32_BITS

#define RGB16_TO_RGB32(p0,p1,v)\
{\
    GLuint g,b,gb;\
    g = (v & 0x07E007E0) << 5;\
    b = (v & 0x001F001F) << 3;\
    gb = g | b;\
    p0 = (gb & 0x0000FFFF) | ((v & 0x0000F800) << 8);\
    p1 = (gb >> 16) | ((v & 0xF8000000) >> 8);\
}

//This function is never called.
static void ZB_copyFrameBufferRGB32(ZBuffer * zb,
                                    void *buf,
                                    GLint linesize)
{
    unsigned short *q;
    GLuint *p, *p1, v, w0, w1;
    GLint y, n;

    q = zb->pbuf;
    p1 = (GLuint *) buf;
	//puts("\nBEING CALLED\n");
    for (y = 0; y < zb->ysize; y++) {
	p = p1;
	n = zb->xsize >> 2;
	do {
	    v = *(GLuint *) q;
	    RGB16_TO_RGB32(w1, w0, v);
	    p[0] = w0;
	    p[1] = w1;
	    v = *(GLuint *) (q + 2);
	    RGB16_TO_RGB32(w1, w0, v);
	    p[2] = w0;
	    p[3] = 0;

	    q += 4;
	    p += 4;
	} while (--n > 0);

	p1 += linesize;
    }
}
*/
#endif

/* 24 bit packed pixel handling */

#ifdef TGL_FEATURE_24_BITS

/* order: RGBR GBRG BRGB */

/* XXX: packed pixel 24 bit support not tested */
/* XXX: big endian case not optimised */
/*
#if BYTE_ORDER == BIG_ENDIAN

#define RGB16_TO_RGB24(p0,p1,p2,v1,v2)\
{\
    GLuint r1,g1,b1,gb1,g2,b2,gb2;\
    v1 = (v1 << 16) | (v1 >> 16);\
    v2 = (v2 << 16) | (v2 >> 16);\
    r1 = (v1 & 0xF800F800);\
    g1 = (v1 & 0x07E007E0) << 5;\
    b1 = (v1 & 0x001F001F) << 3;\
    gb1 = g1 | b1;\
    p0 = ((gb1 & 0x0000FFFF) << 8) | (r1 << 16) | (r1 >> 24);\
    g2 = (v2 & 0x07E007E0) << 5;\
    b2 = (v2 & 0x001F001F) << 3;\
    gb2 = g2 | b2;\
    p1 = (gb1 & 0xFFFF0000) | (v2 & 0xF800) | ((gb2 >> 8) & 0xff);\
    p2 = (gb2 << 24) | ((v2 & 0xF8000000) >> 8) | (gb2 >> 16);\
}

#else

#define RGB16_TO_RGB24(p0,p1,p2,v1,v2)\
{\
    GLuint r1,g1,b1,gb1,g2,b2,gb2;\
    r1 = (v1 & 0xF800F800);\
    g1 = (v1 & 0x07E007E0) << 5;\
    b1 = (v1 & 0x001F001F) << 3;\
    gb1 = g1 | b1;\
    p0 = ((gb1 & 0x0000FFFF) << 8) | (r1 << 16) | (r1 >> 24);\
    g2 = (v2 & 0x07E007E0) << 5;\
    b2 = (v2 & 0x001F001F) << 3;\
    gb2 = g2 | b2;\
    p1 = (gb1 & 0xFFFF0000) | (v2 & 0xF800) | ((gb2 >> 8) & 0xff);\
    p2 = (gb2 << 24) | ((v2 & 0xF8000000) >> 8) | (gb2 >> 16);\
}

#endif
*/
/*
static void ZB_copyFrameBufferRGB24(ZBuffer * zb,
                                    void *buf,
                                    GLint linesize)
{
    unsigned short *q;
    GLuint *p, *p1, w0, w1, w2, v0, v1;
    GLint y, n;

    q = zb->pbuf;
    p1 = (GLuint *) buf;
    linesize = linesize * 3;

    for (y = 0; y < zb->ysize; y++) {
	p = p1;
	n = zb->xsize >> 2;
	do {
	    v0 = *(GLuint *) q;
	    v1 = *(GLuint *) (q + 2);
	    RGB16_TO_RGB24(w0, w1, w2, v0, v1);
	    p[0] = w0;
	    p[1] = w1;
	    p[2] = w2;

	    q += 4;
	    p += 3;
	} while (--n > 0);

	*((GLbyte *) p1) += linesize;
    }
}
*/
#endif

#if TGL_FEATURE_RENDER_BITS == 16


void ZB_copyFrameBuffer(ZBuffer * zb, void *buf,
			int linesize)
{
	
	ZB_copyBuffer(zb, buf, linesize);
		//switch (zb->mode) {
	/*
	#ifdef TGL_FEATURE_8_BITS
		case ZB_MODE_INDEX:
		ZB_ditherFrameBuffer(zb, buf, linesize >> 1);
		break;
	#endif
	*/
	/*#ifdef TGL_FEATURE_16_BITS
		case ZB_MODE_5R6G5B:
		ZB_copyBuffer(zb, buf, linesize);
		break;
	#endif*/


	/*#ifdef TGL_FEATURE_32_BITS
		case ZB_MODE_RGBA:
		ZB_copyFrameBufferRGB32(zb, buf, linesize >> 1);
		break;
	#endif
	*/
	//    default:
	//	assert(0);
	//    }
}

#endif /* TGL_FEATURE_RENDER_BITS == 16 */





/*

#if TGL_FEATURE_RENDER_BITS == 24

#define RGB24_TO_RGB16(r, g, b) \
  ((((r) >> 3) << 11) | (((g) >> 2) << 5) | ((b) >> 3))

// XXX: not optimized 
static void ZB_copyFrameBuffer5R6G5B(ZBuffer * zb, 
                                     void *buf, GLint linesize) 
{
    PIXEL *q;
    unsigned short *p, *p1;
    GLint y, n;

    q = zb->pbuf;
    p1 = (unsigned short *) buf;

    for (y = 0; y < zb->ysize; y++) {
	p = p1;
	n = zb->xsize >> 2;
	do {
            p[0] = RGB24_TO_RGB16(q[0], q[1], q[2]);
            p[1] = RGB24_TO_RGB16(q[3], q[4], q[5]);
            p[2] = RGB24_TO_RGB16(q[6], q[7], q[8]);
            p[3] = RGB24_TO_RGB16(q[9], q[10], q[11]);
	    q = (PIXEL *)((GLbyte *)q + 4 * PSZB);
	    p += 4;
	} while (--n > 0);
	p1 = (unsigned short *)((GLbyte *)p1 + linesize);
    }
}

void ZB_copyFrameBuffer(ZBuffer * zb, void *buf,
			int linesize)
{
    switch (zb->mode) {
#ifdef TGL_FEATURE_16_BITS
    case ZB_MODE_5R6G5B:
	ZB_copyFrameBuffer5R6G5B(zb, buf, linesize);
	break;
#endif
#ifdef TGL_FEATURE_24_BITS
    case ZB_MODE_RGB24:
	ZB_copyBuffer(zb, buf, linesize);
	break;
#endif
    default:
	assert(0);
    }
}

#endif 
*/
/* TGL_FEATURE_RENDER_BITS == 24 
*/

#if TGL_FEATURE_RENDER_BITS == 32

#define RGB32_TO_RGB16(v) \
  (((v >> 8) & 0xf800) | (((v) >> 5) & 0x07e0) | (((v) & 0xff) >> 3))

/* XXX: not optimized */
/*
static void ZB_copyFrameBuffer5R6G5B(ZBuffer * zb, 
                                     void *buf, GLint linesize) 
{
    PIXEL *q;
    unsigned short *p, *p1;
    GLint y, n;

    q = zb->pbuf;
    p1 = (unsigned short *) buf;

    for (y = 0; y < zb->ysize; y++) {
	p = p1;
	n = zb->xsize >> 2;
	do {
            p[0] = RGB32_TO_RGB16(q[0]);
            p[1] = RGB32_TO_RGB16(q[1]);
            p[2] = RGB32_TO_RGB16(q[2]);
            p[3] = RGB32_TO_RGB16(q[3]);
	    q += 4;
	    p += 4;
	} while (--n > 0);
	p1 = (unsigned short *)((GLbyte *)p1 + linesize);
    }
}
*/
void ZB_copyFrameBuffer(ZBuffer * zb, void *buf,
			int linesize)
{
	ZB_copyBuffer(zb, buf, linesize);
    //switch (zb->mode) {
		/*
#ifdef TGL_FEATURE_16_BITS
	case ZB_MODE_5R6G5B:
	ZB_copyFrameBuffer5R6G5B(zb, buf, linesize);
	break;
#endif
		*/
/*
#ifdef TGL_FEATURE_32_BITS
    case ZB_MODE_RGBA:
	ZB_copyBuffer(zb, buf, linesize);
	break;
#endif
    default:
	assert(0);
    }
*/
}

#endif /* TGL_FEATURE_RENDER_BITS == 32 */


/*
 * adr must be aligned on an 'int'
 */
 //Used in 16 bit mode
void memset_s(void *adr, GLint val, GLint count)
{
    GLint i, n, v;
    GLuint *p;
    unsigned short *q;

    p = adr;
    v = val | (val << 16);

    n = count >> 3;
    for (i = 0; i < n; i++) {
	p[0] = v;
	p[1] = v;
	p[2] = v;
	p[3] = v;
	p += 4;
    }

    q = (unsigned short *) p;
    n = count & 7;
    for (i = 0; i < n; i++)
	*q++ = val;
}

//Used in 32 bit mode
void memset_l(void *adr, GLint val, GLint count)
{
    GLint i, n, v;
    GLuint *p;

    p = adr;
    v = val;
    n = count >> 2;
    for (i = 0; i < n; i++) {
	p[0] = v;
	p[1] = v;
	p[2] = v;
	p[3] = v;
	p += 4;
    }

    n = count & 3;
    for (i = 0; i < n; i++)
	*p++ = val;
}

/* count must be a multiple of 4 and >= 4 */
//Gek's note: Should never be used.
void memset_RGB24(void *adr,GLint r, GLint v, GLint b,long count)
{
    long i, n;
    register long v1,v2,v3,*pt=(long *)(adr);
    GLubyte *p,R=(GLubyte)r,V=(GLubyte)v,B=(GLubyte)b;

    p=(GLubyte *)adr;
    *p++=R;
    *p++=V;
    *p++=B;
    *p++=R;
    *p++=V;
    *p++=B;
    *p++=R;
    *p++=V;
    *p++=B;
    *p++=R;
    *p++=V;
    *p++=B;
    v1=*pt++;
    v2=*pt++;
    v3=*pt++;
    n = count >> 2;
    for(i=1;i<n;i++) {
        *pt++=v1;
        *pt++=v2;
        *pt++=v3;
    }
}

void ZB_clear(ZBuffer * zb, GLint clear_z, GLint z,
	      GLint clear_color, GLint r, GLint g, GLint b)
{
#if TGL_FEATURE_RENDER_BITS != 24
    GLint color;
#endif
    GLint y;
    PIXEL *pp;

    if (clear_z) {
	memset_s(zb->zbuf, z, zb->xsize * zb->ysize);
    }
    if (clear_color) {
	pp = zb->pbuf;
	for (y = 0; y < zb->ysize; y++) {
#if TGL_FEATURE_RENDER_BITS == 15 || TGL_FEATURE_RENDER_BITS == 16
            //color = RGB_TO_PIXEL(r, g, b);
         #if TGL_FEATURE_FORCE_CLEAR_NO_COPY_COLOR
         	color = TGL_NO_COPY_COLOR;
         #else
         	color = RGB_TO_PIXEL(r, g, b);
         #endif
	    memset_s(pp, color, zb->xsize);
#elif TGL_FEATURE_RENDER_BITS == 32
		#if TGL_FEATURE_FORCE_CLEAR_NO_COPY_COLOR
			color = TGL_NO_COPY_COLOR;
		#else
            color = RGB_TO_PIXEL(r, g, b);
        #endif
	    memset_l(pp, color, zb->xsize);
#else
#error BADJUJU
#endif
	    pp = (PIXEL *) ((GLbyte *) pp + zb->linesize);
	}
    }
}