[mupen64plus-pandora.git] / source / gles2glide64 / src / Glide64 / DepthBufferRender.cpp

/*
* Glide64 - Glide video plugin for Nintendo 64 emulators.
* Copyright (c) 2002  Dave2001
* Copyright (c) 2003-2009  Sergey 'Gonetz' Lipski
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

//****************************************************************
//
// Glide64 - Glide Plugin for Nintendo 64 emulators
// Project started on December 29th, 2001
//
// Authors:
// Dave2001, original author, founded the project in 2001, left it in 2002
// Gugaman, joined the project in 2002, left it in 2002
// Sergey 'Gonetz' Lipski, joined the project in 2002, main author since fall of 2002
// Hiroshi 'KoolSmoky' Morii, joined the project in 2007
//
//****************************************************************
//
// To modify Glide64:
// * Write your name and (optional)email, commented by your work, so I know who did it, and so that you can find which parts you modified when it comes time to send it to me.
// * Do NOT send me the whole project or file that you modified.  Take out your modified code sections, and tell me where to put them.  If people sent the whole thing, I would have many different versions, but no idea how to combine them all.
//
//****************************************************************
//
// Software rendering into N64 depth buffer
// Idea and N64 depth value format by Orkin
// Polygon rasterization algorithm is taken from FATMAP2 engine by Mats Byggmastar, mri@penti.sit.fi
//
// Created by Gonetz, Dec 2004
//
//****************************************************************

#include "Gfx_1.3.h"
#include "rdp.h"
#include "DepthBufferRender.h"

wxUint16 * zLUT = 0;

void ZLUT_init()
{
  if (zLUT)
    return;
  zLUT = new wxUint16[0x40000];
  for(int i=0; i<0x40000; i++)
  {
    wxUint32 exponent = 0;
    wxUint32 testbit = 1 << 17;
    while((i & testbit) && (exponent < 7))
    {
      exponent++;
      testbit = 1 << (17 - exponent);
    }
    
    wxUint32 mantissa = (i >> (6 - (6 < exponent ? 6 : exponent))) & 0x7ff;
    zLUT[i] = (wxUint16)(((exponent << 11) | mantissa) << 2);
  }
}

void ZLUT_release()
{
  delete[] zLUT;
  zLUT = 0;
}

static vertexi * max_vtx;                   // Max y vertex (ending vertex)
static vertexi * start_vtx, * end_vtx;      // First and last vertex in array
static vertexi * right_vtx, * left_vtx;     // Current right and left vertex

#ifdef HAVE_GLES
// using float should be faster than int in fact, especialy if using NEON
static float right_height, left_height;
static float right_x, right_dxdy, left_x, left_dxdy;
static float left_z, left_dzdy;

__inline float iceil(int x)
{
	return cellf((float)x*(1.0f/65536.0f));
}
__inline float i2float(int x)
{
	return (float)x*(1.0f/65536.0f);
}
__inline int float2i(float x)
{
	return x*65536.0f;
}

#else

static int right_height, left_height;
static int right_x, right_dxdy, left_x, left_dxdy;
static int left_z, left_dzdy;

__inline int imul16(int x, int y)        // (x * y) >> 16
{
    return (((long long)x) * ((long long)y)) >> 16;
}

__inline int imul14(int x, int y)        // (x * y) >> 14
{
    return (((long long)x) * ((long long)y)) >> 14;
}
__inline int idiv16(int x, int y)        // (x << 16) / y
{
    //x = (((long long)x) << 16) / ((long long)y);
 /*   
  eax = x;
  ebx = y;
  edx = x;
  (x << 16) | ()
   */ 
#if !defined(__GNUC__) && !defined(NO_ASM)
  __asm {
        mov   eax, x
        mov   ebx, y
        mov   edx,eax   
        sar   edx,16
        shl   eax,16    
        idiv  ebx  
        mov   x, eax
    }
#elif !defined(NO_ASM)
    int reminder;
    asm ("idivl %[divisor]"
          : "=a" (x), "=d" (reminder)
          : [divisor] "g" (y), "d" (x >> 16), "a" (x << 16));
#else
	x = (((long long)x) << 16) / ((long long)y);
#endif
    return x;
}

__inline int iceil(int x)
{
  x +=  0xffff;
  return (x >> 16);
}
#endif

static void RightSection(void)
{
  // Walk backwards trough the vertex array
  
  vertexi * v2, * v1 = right_vtx;
  if(right_vtx > start_vtx) v2 = right_vtx-1;     
  else                      v2 = end_vtx;         // Wrap to end of array
  right_vtx = v2;
  
  // v1 = top vertex
  // v2 = bottom vertex 
  
  // Calculate number of scanlines in this section
  
  right_height = iceil(v2->y) - iceil(v1->y);
  if(right_height <= 0) return;
  
  // Guard against possible div overflows
  
  #ifdef HAVE_GLES
  right_dxdy  = i2float(v2->x - v1->x)/i2float(v2->y - v1->y);
  #else
  if(right_height > 1) {
    // OK, no worries, we have a section that is at least
    // one pixel high. Calculate slope as usual.
    
    int height = v2->y - v1->y;
    right_dxdy  = idiv16(v2->x - v1->x, height);
  }
  else {
    // Height is less or equal to one pixel.
    // Calculate slope = width * 1/height
    // using 18:14 bit precision to avoid overflows.
    
    int inv_height = (0x10000 << 14) / (v2->y - v1->y);  
    right_dxdy = imul14(v2->x - v1->x, inv_height);
  }
  #endif
  
  // Prestep initial values
  
  #ifdef HAVE_GLES
  float prestep = iceil(v1->y) - i2float(v1->y);
  right_x = i2float(v1->x) + prestep*right_dxdy;
  #else
  int prestep = (iceil(v1->y) << 16) - v1->y;
  right_x = v1->x + imul16(prestep, right_dxdy);
  #endif
}

static void LeftSection(void)
{
  // Walk forward trough the vertex array
  
  vertexi * v2, * v1 = left_vtx;
  if(left_vtx < end_vtx) v2 = left_vtx+1;
  else                   v2 = start_vtx;      // Wrap to start of array
  left_vtx = v2;
  
  // v1 = top vertex
  // v2 = bottom vertex 
  
  // Calculate number of scanlines in this section
  
  left_height = iceil(v2->y) - iceil(v1->y);
  if(left_height <= 0) return;
  
  // Guard against possible div overflows
  
  #ifdef HAVE_GLES
  float invheight = 1.0f/i2float(v2->y - v1->y)
  left_dxdy  = i2float(v2->x - v1->x)*invheight;
  left_dzdy  = i2float(v2->z - v1->z)*invheight;
  #else
  if(left_height > 1) {
    // OK, no worries, we have a section that is at least
    // one pixel high. Calculate slope as usual.
    
    int height = v2->y - v1->y;
    left_dxdy = idiv16(v2->x - v1->x, height);
    left_dzdy = idiv16(v2->z - v1->z, height);
  }
  else {
    // Height is less or equal to one pixel.
    // Calculate slope = width * 1/height
    // using 18:14 bit precision to avoid overflows.
    
    int inv_height = (0x10000 << 14) / (v2->y - v1->y);
    left_dxdy = imul14(v2->x - v1->x, inv_height);
    left_dzdy = imul14(v2->z - v1->z, inv_height);
  }
  #endif
  
  // Prestep initial values
  
  #ifdef HAVE_GLES
  float prestep = iceil(v1->y) - i2float(v1->y);
  left_x = i2float(v1->x) + prestep*left_dxdy;
  left_z = i2float(v1->z) + prestep*left_dzdy;
  #else
  int prestep = (iceil(v1->y) << 16) - v1->y;
  left_x = v1->x + imul16(prestep, left_dxdy);
  left_z = v1->z + imul16(prestep, left_dzdy);
  #endif
}


void Rasterize(vertexi * vtx, int vertices, int dzdx)
{
  start_vtx = vtx;        // First vertex in array
  
  // Search trough the vtx array to find min y, max y
  // and the location of these structures.
  
  vertexi * min_vtx = vtx;
  max_vtx = vtx;
  
  int min_y = vtx->y;
  int max_y = vtx->y;
  
  vtx++;
  
  for(int n=1; n<vertices; n++) {
    if(vtx->y < min_y) {
      min_y = vtx->y;
      min_vtx = vtx;
    }
    else
      if(vtx->y > max_y) {
        max_y = vtx->y;
        max_vtx = vtx;
      }
      vtx++;
  }
  
  // OK, now we know where in the array we should start and
  // where to end while scanning the edges of the polygon
  
  left_vtx  = min_vtx;    // Left side starting vertex
  right_vtx = min_vtx;    // Right side starting vertex
  end_vtx   = vtx-1;      // Last vertex in array
  
  // Search for the first usable right section
  
  do {
    if(right_vtx == max_vtx) return;
    RightSection();
  } while(right_height <= 0);
  
  // Search for the first usable left section
  
  do {
    if(left_vtx == max_vtx) return;
    LeftSection();
  } while(left_height <= 0);
  
  wxUint16 * destptr = (wxUint16*)(gfx.RDRAM+rdp.zimg);
  int y1 = iceil(min_y);
  if (y1 >= (int)rdp.scissor_o.lr_y) return;
  int shift;
  
  for(;;)
  {
    int x1 = iceil(left_x);
    if (x1 < (int)rdp.scissor_o.ul_x)
      x1 = rdp.scissor_o.ul_x;
    int width = iceil(right_x) - x1;
    if (x1+width >= (int)rdp.scissor_o.lr_x)
      width = rdp.scissor_o.lr_x - x1 - 1;

    if(width > 0 && y1 >= (int)rdp.scissor_o.ul_y) {
  
        
      // Prestep initial z
      
	  #ifdef HAVE_GLES
      float z = left_z + (x1 - left_x)*dzdx;
	  #else
      int prestep = (x1 << 16) - left_x;
      int z = left_z + imul16(prestep, dzdx);
	  #endif
      
      shift = x1 + y1*rdp.zi_width;
      //draw to depth buffer
      int trueZ;
      int idx;
      wxUint16 encodedZ;
      for (int x = 0; x < width; x++)
      {
		#ifdef HAVE_GLES
		trueZ = (int)(z*8.0f);
		#else
        trueZ = z/8192;
		#endif
        if (trueZ < 0) trueZ = 0;
        else if (trueZ > 0x3FFFF) trueZ = 0x3FFFF;
        encodedZ = zLUT[trueZ];
        idx = (shift+x)^1;
        if(encodedZ < destptr[idx]) 
          destptr[idx] = encodedZ;
        z += dzdx;
      }
    }
    
    //destptr += rdp.zi_width;
    y1++;
    if (y1 >= (int)rdp.scissor_o.lr_y) return;
    
    // Scan the right side
    
    if(--right_height <= 0) {               // End of this section?
      do {
        if(right_vtx == max_vtx) return;
        RightSection();
      } while(right_height <= 0);
    }
    else 
      right_x += right_dxdy;
    
    // Scan the left side
    
    if(--left_height <= 0) {                // End of this section?
      do {
        if(left_vtx == max_vtx) return;
        LeftSection();
      } while(left_height <= 0);
    }
    else {
      left_x += left_dxdy;
      left_z += left_dzdy;
    }
  }
}
Commit	Line	Data
98e75f2d	1	/*
	2	* Glide64 - Glide video plugin for Nintendo 64 emulators.
	3	* Copyright (c) 2002 Dave2001
	4	* Copyright (c) 2003-2009 Sergey 'Gonetz' Lipski
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	19	*/
	20
	21	//****************************************************************
	22	//
	23	// Glide64 - Glide Plugin for Nintendo 64 emulators
	24	// Project started on December 29th, 2001
	25	//
	26	// Authors:
	27	// Dave2001, original author, founded the project in 2001, left it in 2002
	28	// Gugaman, joined the project in 2002, left it in 2002
	29	// Sergey 'Gonetz' Lipski, joined the project in 2002, main author since fall of 2002
	30	// Hiroshi 'KoolSmoky' Morii, joined the project in 2007
	31	//
	32	//****************************************************************
	33	//
	34	// To modify Glide64:
	35	// * Write your name and (optional)email, commented by your work, so I know who did it, and so that you can find which parts you modified when it comes time to send it to me.
	36	// * Do NOT send me the whole project or file that you modified. Take out your modified code sections, and tell me where to put them. If people sent the whole thing, I would have many different versions, but no idea how to combine them all.
	37	//
	38	//****************************************************************
	39	//
	40	// Software rendering into N64 depth buffer
	41	// Idea and N64 depth value format by Orkin
	42	// Polygon rasterization algorithm is taken from FATMAP2 engine by Mats Byggmastar, mri@penti.sit.fi
	43	//
	44	// Created by Gonetz, Dec 2004
	45	//
	46	//****************************************************************
	47
	48	#include "Gfx_1.3.h"
	49	#include "rdp.h"
	50	#include "DepthBufferRender.h"
	51
	52	wxUint16 * zLUT = 0;
	53
	54	void ZLUT_init()
	55	{
	56	if (zLUT)
	57	return;
	58	zLUT = new wxUint16[0x40000];
	59	for(int i=0; i<0x40000; i++)
	60	{
	61	wxUint32 exponent = 0;
	62	wxUint32 testbit = 1 << 17;
	63	while((i & testbit) && (exponent < 7))
	64	{
65	exponent++;
66	testbit = 1 << (17 - exponent);
67	}
68
69	wxUint32 mantissa = (i >> (6 - (6 < exponent ? 6 : exponent))) & 0x7ff;
70	zLUT[i] = (wxUint16)(((exponent << 11) \| mantissa) << 2);
71	}
72	}
73
74	void ZLUT_release()
75	{
76	delete[] zLUT;
77	zLUT = 0;
78	}
79
80	static vertexi * max_vtx; // Max y vertex (ending vertex)
81	static vertexi * start_vtx, * end_vtx; // First and last vertex in array
82	static vertexi * right_vtx, * left_vtx; // Current right and left vertex
83
84	#ifdef HAVE_GLES
85	// using float should be faster than int in fact, especialy if using NEON
86	static float right_height, left_height;
87	static float right_x, right_dxdy, left_x, left_dxdy;
88	static float left_z, left_dzdy;
89
90	__inline float iceil(int x)
91	{
92	return cellf((float)x*(1.0f/65536.0f));
93	}
94	__inline float i2float(int x)
95	{
96	return (float)x*(1.0f/65536.0f);
97	}
98	__inline int float2i(float x)
99	{
100	return x*65536.0f;
101	}
102
103	#else
104
105	static int right_height, left_height;
106	static int right_x, right_dxdy, left_x, left_dxdy;
107	static int left_z, left_dzdy;
108
109	__inline int imul16(int x, int y) // (x * y) >> 16
110	{
111	return (((long long)x) * ((long long)y)) >> 16;
112	}
113
114	__inline int imul14(int x, int y) // (x * y) >> 14
115	{
116	return (((long long)x) * ((long long)y)) >> 14;
117	}
118	__inline int idiv16(int x, int y) // (x << 16) / y
119	{
120	//x = (((long long)x) << 16) / ((long long)y);
121	/*
122	eax = x;
123	ebx = y;
124	edx = x;
125	(x << 16) \| ()
126	*/
127	#if !defined(__GNUC__) && !defined(NO_ASM)
128	__asm {
129	mov eax, x
130	mov ebx, y
131	mov edx,eax
132	sar edx,16
133	shl eax,16
134	idiv ebx
135	mov x, eax
136	}
137	#elif !defined(NO_ASM)
138	int reminder;
139	asm ("idivl %[divisor]"
140	: "=a" (x), "=d" (reminder)
141	: [divisor] "g" (y), "d" (x >> 16), "a" (x << 16));
142	#else
143	x = (((long long)x) << 16) / ((long long)y);
144	#endif
145	return x;
146	}
147
148	__inline int iceil(int x)
149	{
150	x += 0xffff;
151	return (x >> 16);
152	}
153	#endif
154
155	static void RightSection(void)
156	{
157	// Walk backwards trough the vertex array
158
159	vertexi * v2, * v1 = right_vtx;
160	if(right_vtx > start_vtx) v2 = right_vtx-1;
161	else v2 = end_vtx; // Wrap to end of array
162	right_vtx = v2;
163
164	// v1 = top vertex
165	// v2 = bottom vertex
166
167	// Calculate number of scanlines in this section
168
169	right_height = iceil(v2->y) - iceil(v1->y);
170	if(right_height <= 0) return;
171
172	// Guard against possible div overflows
173
174	#ifdef HAVE_GLES
175	right_dxdy = i2float(v2->x - v1->x)/i2float(v2->y - v1->y);
176	#else
177	if(right_height > 1) {
178	// OK, no worries, we have a section that is at least
179	// one pixel high. Calculate slope as usual.
180
181	int height = v2->y - v1->y;
182	right_dxdy = idiv16(v2->x - v1->x, height);
183	}
184	else {
185	// Height is less or equal to one pixel.
186	// Calculate slope = width * 1/height
187	// using 18:14 bit precision to avoid overflows.
188
189	int inv_height = (0x10000 << 14) / (v2->y - v1->y);
190	right_dxdy = imul14(v2->x - v1->x, inv_height);
191	}
192	#endif
193
194	// Prestep initial values
195
196	#ifdef HAVE_GLES
197	float prestep = iceil(v1->y) - i2float(v1->y);
198	right_x = i2float(v1->x) + prestep*right_dxdy;
199	#else
200	int prestep = (iceil(v1->y) << 16) - v1->y;
201	right_x = v1->x + imul16(prestep, right_dxdy);
202	#endif
203	}
204
205	static void LeftSection(void)
206	{
207	// Walk forward trough the vertex array
208
209	vertexi * v2, * v1 = left_vtx;
210	if(left_vtx < end_vtx) v2 = left_vtx+1;
211	else v2 = start_vtx; // Wrap to start of array
212	left_vtx = v2;
213
214	// v1 = top vertex
215	// v2 = bottom vertex
216
217	// Calculate number of scanlines in this section
218
219	left_height = iceil(v2->y) - iceil(v1->y);
220	if(left_height <= 0) return;
221
222	// Guard against possible div overflows
223
224	#ifdef HAVE_GLES
225	float invheight = 1.0f/i2float(v2->y - v1->y)
226	left_dxdy = i2float(v2->x - v1->x)*invheight;
227	left_dzdy = i2float(v2->z - v1->z)*invheight;
228	#else
229	if(left_height > 1) {
230	// OK, no worries, we have a section that is at least
231	// one pixel high. Calculate slope as usual.
232
233	int height = v2->y - v1->y;
234	left_dxdy = idiv16(v2->x - v1->x, height);
235	left_dzdy = idiv16(v2->z - v1->z, height);
236	}
237	else {
238	// Height is less or equal to one pixel.
239	// Calculate slope = width * 1/height
240	// using 18:14 bit precision to avoid overflows.
241
242	int inv_height = (0x10000 << 14) / (v2->y - v1->y);
243	left_dxdy = imul14(v2->x - v1->x, inv_height);
244	left_dzdy = imul14(v2->z - v1->z, inv_height);
245	}
246	#endif
247
248	// Prestep initial values
249
250	#ifdef HAVE_GLES
251	float prestep = iceil(v1->y) - i2float(v1->y);
252	left_x = i2float(v1->x) + prestep*left_dxdy;
253	left_z = i2float(v1->z) + prestep*left_dzdy;
254	#else
255	int prestep = (iceil(v1->y) << 16) - v1->y;
256	left_x = v1->x + imul16(prestep, left_dxdy);
257	left_z = v1->z + imul16(prestep, left_dzdy);
258	#endif
259	}
260
261
262	void Rasterize(vertexi * vtx, int vertices, int dzdx)
263	{
264	start_vtx = vtx; // First vertex in array
265
266	// Search trough the vtx array to find min y, max y
267	// and the location of these structures.
268
269	vertexi * min_vtx = vtx;
270	max_vtx = vtx;
271
272	int min_y = vtx->y;
273	int max_y = vtx->y;
274
275	vtx++;
276
277	for(int n=1; n<vertices; n++) {
278	if(vtx->y < min_y) {
279	min_y = vtx->y;
280	min_vtx = vtx;
281	}
282	else
283	if(vtx->y > max_y) {
284	max_y = vtx->y;
285	max_vtx = vtx;
286	}
287	vtx++;
288	}
289
290	// OK, now we know where in the array we should start and
291	// where to end while scanning the edges of the polygon
292
293	left_vtx = min_vtx; // Left side starting vertex
294	right_vtx = min_vtx; // Right side starting vertex
295	end_vtx = vtx-1; // Last vertex in array
296
297	// Search for the first usable right section
298
299	do {
300	if(right_vtx == max_vtx) return;
301	RightSection();
302	} while(right_height <= 0);
303
304	// Search for the first usable left section
305
306	do {
307	if(left_vtx == max_vtx) return;
308	LeftSection();
309	} while(left_height <= 0);
310
311	wxUint16 * destptr = (wxUint16*)(gfx.RDRAM+rdp.zimg);
312	int y1 = iceil(min_y);
313	if (y1 >= (int)rdp.scissor_o.lr_y) return;
314	int shift;
315
316	for(;;)
317	{
318	int x1 = iceil(left_x);
319	if (x1 < (int)rdp.scissor_o.ul_x)
320	x1 = rdp.scissor_o.ul_x;
321	int width = iceil(right_x) - x1;
322	if (x1+width >= (int)rdp.scissor_o.lr_x)
323	width = rdp.scissor_o.lr_x - x1 - 1;
324
325	if(width > 0 && y1 >= (int)rdp.scissor_o.ul_y) {
326
327
328	// Prestep initial z
329
330	#ifdef HAVE_GLES
331	float z = left_z + (x1 - left_x)*dzdx;
332	#else
333	int prestep = (x1 << 16) - left_x;
334	int z = left_z + imul16(prestep, dzdx);
335	#endif
336
337	shift = x1 + y1*rdp.zi_width;
338	//draw to depth buffer
339	int trueZ;
340	int idx;
341	wxUint16 encodedZ;
342	for (int x = 0; x < width; x++)
343	{
344	#ifdef HAVE_GLES
345	trueZ = (int)(z*8.0f);
346	#else
347	trueZ = z/8192;
348	#endif
349	if (trueZ < 0) trueZ = 0;
350	else if (trueZ > 0x3FFFF) trueZ = 0x3FFFF;
351	encodedZ = zLUT[trueZ];
352	idx = (shift+x)^1;
353	if(encodedZ < destptr[idx])
354	destptr[idx] = encodedZ;
355	z += dzdx;
356	}
357	}
358
359	//destptr += rdp.zi_width;
360	y1++;
361	if (y1 >= (int)rdp.scissor_o.lr_y) return;
362
363	// Scan the right side
364
365	if(--right_height <= 0) { // End of this section?
366	do {
367	if(right_vtx == max_vtx) return;
368	RightSection();
369	} while(right_height <= 0);
370	}
371	else
372	right_x += right_dxdy;
373
374	// Scan the left side
375
376	if(--left_height <= 0) { // End of this section?
377	do {
378	if(left_vtx == max_vtx) return;
379	LeftSection();
380	} while(left_height <= 0);
381	}
382	else {
383	left_x += left_dxdy;
384	left_z += left_dzdy;
385	}
386	}
387	}