depth.c File Reference

#include <stdlib.h>
#include <string.h>
#include "context.h"
#include "depth.h"
#include "dlist.h"
#include "macros.h"
#include "types.h"

Include dependency graph for depth.c:

Go to the source code of this file.

Macros
#define	ZADDR_SETUP
#define	ZADDR(X, Y)   (depthbuffer + (Y) * width + (X) )

Functions
void	gl_ClearDepth (GLcontext *ctx, GLclampd depth)
void	gl_DepthFunc (GLcontext *ctx, GLenum func)
void	gl_DepthMask (GLcontext *ctx, GLboolean flag)
void	gl_DepthRange (GLcontext *ctx, GLclampd nearval, GLclampd farval)
GLuint	gl_depth_test_span_generic (GLcontext *ctx, GLuint n, GLint x, GLint y, const GLdepth z[], GLubyte mask[])
GLuint	gl_depth_test_span_less (GLcontext *ctx, GLuint n, GLint x, GLint y, const GLdepth z[], GLubyte mask[])
GLuint	gl_depth_test_span_greater (GLcontext *ctx, GLuint n, GLint x, GLint y, const GLdepth z[], GLubyte mask[])
void	gl_depth_test_pixels_generic (GLcontext *ctx, GLuint n, const GLint x[], const GLint y[], const GLdepth z[], GLubyte mask[])
void	gl_depth_test_pixels_less (GLcontext *ctx, GLuint n, const GLint x[], const GLint y[], const GLdepth z[], GLubyte mask[])
void	gl_depth_test_pixels_greater (GLcontext *ctx, GLuint n, const GLint x[], const GLint y[], const GLdepth z[], GLubyte mask[])
void	gl_read_depth_span_float (GLcontext *ctx, GLuint n, GLint x, GLint y, GLfloat depth[])
void	gl_read_depth_span_int (GLcontext *ctx, GLuint n, GLint x, GLint y, GLdepth depth[])
void	gl_alloc_depth_buffer (GLcontext *ctx)
void	gl_clear_depth_buffer (GLcontext *ctx)

Macro Definition Documentation

ZADDR

#define ZADDR	(		X,
			Y
	)		(depthbuffer + (Y) * width + (X) )

Definition at line 482 of file depth.c.

ZADDR_SETUP

#define ZADDR_SETUP

Value:

                      GLdepth *depthbuffer = ctx->Buffer->Depth; \
                      GLint width = ctx->Buffer->Width;

Definition at line 479 of file depth.c.

Function Documentation

gl_alloc_depth_buffer()

void gl_alloc_depth_buffer

(

GLcontext *

ctx

)

Definition at line 848 of file depth.c.

{
   /* deallocate current depth buffer if present */
   if (ctx->Buffer->Depth) {
      free(ctx->Buffer->Depth);
      ctx->Buffer->Depth = NULL;
   }
 
   /* allocate new depth buffer, but don't initialize it */
   ctx->Buffer->Depth = (GLdepth *) malloc( ctx->Buffer->Width
                                            * ctx->Buffer->Height
                                            * sizeof(GLdepth) );
   if (!ctx->Buffer->Depth) {
      /* out of memory */
      ctx->Depth.Test = GL_FALSE;
      gl_error( ctx, GL_OUT_OF_MEMORY, "Couldn't allocate depth buffer" );
   }
}

Referenced by gl_update_state().

gl_clear_depth_buffer()

void gl_clear_depth_buffer

(

GLcontext *

ctx

)

Definition at line 875 of file depth.c.

{
   GLdepth clear_value = (GLdepth) (ctx->Depth.Clear * DEPTH_SCALE);
 
   if (ctx->Visual->DepthBits==0 || !ctx->Buffer->Depth) {
      /* no depth buffer */
      return;
   }
 
   /* The loops in this function have been written so the IRIX 5.3
    * C compiler can unroll them.  Hopefully other compilers can too!
    */
 
   if (ctx->Scissor.Enabled) {
      /* only clear scissor region */
      GLint y;
      for (y=ctx->Buffer->Ymin; y<=ctx->Buffer->Ymax; y++) {
         GLdepth *d = Z_ADDRESS( ctx, ctx->Buffer->Xmin, y );
         GLint n = ctx->Buffer->Xmax - ctx->Buffer->Xmin + 1;
         do {
            *d++ = clear_value;
            n--;
         } while (n);
      }
   }
   else {
      /* clear whole buffer */
      GLdepth *d = ctx->Buffer->Depth;
      GLint n = ctx->Buffer->Width * ctx->Buffer->Height;
      while (n>=16) {
         d[0] = clear_value;    d[1] = clear_value;
         d[2] = clear_value;    d[3] = clear_value;
         d[4] = clear_value;    d[5] = clear_value;
         d[6] = clear_value;    d[7] = clear_value;
         d[8] = clear_value;    d[9] = clear_value;
         d[10] = clear_value;   d[11] = clear_value;
         d[12] = clear_value;   d[13] = clear_value;
         d[14] = clear_value;   d[15] = clear_value;
         d += 16;
         n -= 16;
      }
      while (n>0) {
         *d++ = clear_value;
         n--;
      }
   }
}

Referenced by gl_update_state().

gl_ClearDepth()

void gl_ClearDepth	(	GLcontext *	ctx,
		GLclampd	depth
	)

Definition at line 87 of file depth.c.

{
   if (INSIDE_BEGIN_END(ctx)) {
      gl_error( ctx, GL_INVALID_OPERATION, "glClearDepth" );
      return;
   }
   ctx->Depth.Clear = (GLfloat) CLAMP( depth, 0.0, 1.0 );
}

Referenced by execute_list(), and init_exec_pointers().

gl_depth_test_pixels_generic()

void gl_depth_test_pixels_generic	(	GLcontext *	ctx,
		GLuint	n,
		const GLint	x[],
		const GLint	y[],
		const GLdepth	z[],
		GLubyte	mask[]
	)

Definition at line 489 of file depth.c.

{
   register GLdepth *zptr;
   register GLuint i;
 
   /* switch cases ordered from most frequent to less frequent */
   switch (ctx->Depth.Func) {
      case GL_LESS:
         if (ctx->Depth.Mask) {
        /* Update Z buffer */
        for (i=0; i<n; i++) {
           if (mask[i]) {
          zptr = Z_ADDRESS(ctx,x[i],y[i]);
          if (z[i] < *zptr) {
             /* pass */
             *zptr = z[i];
          }
          else {
             /* fail */
             mask[i] = 0;
          }
           }
        }
     }
     else {
        /* Don't update Z buffer */
        for (i=0; i<n; i++) {
           if (mask[i]) {
          zptr = Z_ADDRESS(ctx,x[i],y[i]);
          if (z[i] < *zptr) {
             /* pass */
          }
          else {
             /* fail */
             mask[i] = 0;
          }
           }
        }
     }
     break;
      case GL_LEQUAL:
         if (ctx->Depth.Mask) {
        /* Update Z buffer */
        for (i=0; i<n; i++) {
           if (mask[i]) {
          zptr = Z_ADDRESS(ctx,x[i],y[i]);
          if (z[i] <= *zptr) {
             /* pass */
             *zptr = z[i];
          }
          else {
             /* fail */
             mask[i] = 0;
          }
           }
        }
     }
     else {
        /* Don't update Z buffer */
        for (i=0; i<n; i++) {
           if (mask[i]) {
          zptr = Z_ADDRESS(ctx,x[i],y[i]);
          if (z[i] <= *zptr) {
             /* pass */
          }
          else {
             /* fail */
             mask[i] = 0;
          }
           }
        }
     }
     break;
      case GL_GEQUAL:
         if (ctx->Depth.Mask) {
        /* Update Z buffer */
        for (i=0; i<n; i++) {
           if (mask[i]) {
          zptr = Z_ADDRESS(ctx,x[i],y[i]);
          if (z[i] >= *zptr) {
             /* pass */
             *zptr = z[i];
          }
          else {
             /* fail */
             mask[i] = 0;
          }
           }
        }
     }
     else {
        /* Don't update Z buffer */
        for (i=0; i<n; i++) {
           if (mask[i]) {
          zptr = Z_ADDRESS(ctx,x[i],y[i]);
          if (z[i] >= *zptr) {
             /* pass */
          }
          else {
             /* fail */
             mask[i] = 0;
          }
           }
        }
     }
     break;
      case GL_GREATER:
         if (ctx->Depth.Mask) {
        /* Update Z buffer */
        for (i=0; i<n; i++) {
           if (mask[i]) {
          zptr = Z_ADDRESS(ctx,x[i],y[i]);
          if (z[i] > *zptr) {
             /* pass */
             *zptr = z[i];
          }
          else {
             /* fail */
             mask[i] = 0;
          }
           }
        }
     }
     else {
        /* Don't update Z buffer */
        for (i=0; i<n; i++) {
           if (mask[i]) {
          zptr = Z_ADDRESS(ctx,x[i],y[i]);
          if (z[i] > *zptr) {
             /* pass */
          }
          else {
             /* fail */
             mask[i] = 0;
          }
           }
        }
     }
     break;
      case GL_NOTEQUAL:
         if (ctx->Depth.Mask) {
        /* Update Z buffer */
        for (i=0; i<n; i++) {
           if (mask[i]) {
          zptr = Z_ADDRESS(ctx,x[i],y[i]);
          if (z[i] != *zptr) {
             /* pass */
             *zptr = z[i];
          }
          else {
             /* fail */
             mask[i] = 0;
          }
           }
        }
     }
     else {
        /* Don't update Z buffer */
        for (i=0; i<n; i++) {
           if (mask[i]) {
          zptr = Z_ADDRESS(ctx,x[i],y[i]);
          if (z[i] != *zptr) {
             /* pass */
          }
          else {
             /* fail */
             mask[i] = 0;
          }
           }
        }
     }
     break;
      case GL_EQUAL:
         if (ctx->Depth.Mask) {
        /* Update Z buffer */
        for (i=0; i<n; i++) {
           if (mask[i]) {
          zptr = Z_ADDRESS(ctx,x[i],y[i]);
          if (z[i] == *zptr) {
             /* pass */
             *zptr = z[i];
          }
          else {
             /* fail */
             mask[i] = 0;
          }
           }
        }
     }
     else {
        /* Don't update Z buffer */
        for (i=0; i<n; i++) {
           if (mask[i]) {
          zptr = Z_ADDRESS(ctx,x[i],y[i]);
          if (z[i] == *zptr) {
             /* pass */
          }
          else {
             /* fail */
             mask[i] = 0;
          }
           }
        }
     }
     break;
      case GL_ALWAYS:
     if (ctx->Depth.Mask) {
        /* Update Z buffer */
        for (i=0; i<n; i++) {
           if (mask[i]) {
          zptr = Z_ADDRESS(ctx,x[i],y[i]);
          *zptr = z[i];
           }
        }
     }
     else {
        /* Don't update Z buffer or mask */
     }
     break;
      case GL_NEVER:
     /* depth test never passes */
     for (i=0;i<n;i++) {
        mask[i] = 0;
     }
     break;
      default:
         gl_problem(ctx, "Bad depth func in gl_depth_test_pixels_generic");
   } /*switch*/
}

Referenced by gl_update_state().

gl_depth_test_pixels_greater()

void gl_depth_test_pixels_greater	(	GLcontext *	ctx,
		GLuint	n,
		const GLint	x[],
		const GLint	y[],
		const GLdepth	z[],
		GLubyte	mask[]
	)

Definition at line 752 of file depth.c.

{
   GLdepth *zptr;
   GLuint i;
 
   for (i=0; i<n; i++) {
      if (mask[i]) {
         zptr = Z_ADDRESS(ctx,x[i],y[i]);
         if (z[i] > *zptr) {
            /* pass */
            *zptr = z[i];
         }
         else {
            /* fail */
            mask[i] = 0;
         }
      }
   }
}

Referenced by gl_update_state().

gl_depth_test_pixels_less()

void gl_depth_test_pixels_less	(	GLcontext *	ctx,
		GLuint	n,
		const GLint	x[],
		const GLint	y[],
		const GLdepth	z[],
		GLubyte	mask[]
	)

Definition at line 726 of file depth.c.

{
   GLdepth *zptr;
   GLuint i;
 
   for (i=0; i<n; i++) {
      if (mask[i]) {
         zptr = Z_ADDRESS(ctx,x[i],y[i]);
         if (z[i] < *zptr) {
            /* pass */
            *zptr = z[i];
         }
         else {
            /* fail */
            mask[i] = 0;
         }
      }
   }
}

Referenced by gl_update_state().

gl_depth_test_span_generic()

GLuint gl_depth_test_span_generic	(	GLcontext *	ctx,
		GLuint	n,
		GLint	x,
		GLint	y,
		const GLdepth	z[],
		GLubyte	mask[]
	)

Definition at line 193 of file depth.c.

{
   GLdepth *zptr = Z_ADDRESS( ctx, x, y );
   GLubyte *m = mask;
   GLuint i;
   GLuint passed = 0;
 
   /* switch cases ordered from most frequent to less frequent */
   switch (ctx->Depth.Func) {
      case GL_LESS:
         if (ctx->Depth.Mask) {
        /* Update Z buffer */
        for (i=0; i<n; i++,zptr++,m++) {
           if (*m) {
          if (z[i] < *zptr) {
             /* pass */
             *zptr = z[i];
             passed++;
          }
          else {
             /* fail */
             *m = 0;
          }
           }
        }
     }
     else {
        /* Don't update Z buffer */
        for (i=0; i<n; i++,zptr++,m++) {
           if (*m) {
          if (z[i] < *zptr) {
             /* pass */
             passed++;
          }
          else {
             *m = 0;
          }
           }
        }
     }
     break;
      case GL_LEQUAL:
     if (ctx->Depth.Mask) {
        /* Update Z buffer */
        for (i=0;i<n;i++,zptr++,m++) {
           if (*m) {
          if (z[i] <= *zptr) {
             *zptr = z[i];
             passed++;
          }
          else {
             *m = 0;
          }
           }
        }
     }
     else {
        /* Don't update Z buffer */
        for (i=0;i<n;i++,zptr++,m++) {
           if (*m) {
          if (z[i] <= *zptr) {
             /* pass */
             passed++;
          }
          else {
             *m = 0;
          }
           }
        }
     }
     break;
      case GL_GEQUAL:
     if (ctx->Depth.Mask) {
        /* Update Z buffer */
        for (i=0;i<n;i++,zptr++,m++) {
           if (*m) {
          if (z[i] >= *zptr) {
             *zptr = z[i];
             passed++;
          }
          else {
             *m = 0;
          }
           }
        }
     }
     else {
        /* Don't update Z buffer */
        for (i=0;i<n;i++,zptr++,m++) {
           if (*m) {
          if (z[i] >= *zptr) {
             /* pass */
             passed++;
          }
          else {
             *m = 0;
          }
           }
        }
     }
     break;
      case GL_GREATER:
     if (ctx->Depth.Mask) {
        /* Update Z buffer */
        for (i=0;i<n;i++,zptr++,m++) {
           if (*m) {
          if (z[i] > *zptr) {
             *zptr = z[i];
             passed++;
          }
          else {
             *m = 0;
          }
           }
        }
     }
     else {
        /* Don't update Z buffer */
        for (i=0;i<n;i++,zptr++,m++) {
           if (*m) {
          if (z[i] > *zptr) {
             /* pass */
             passed++;
          }
          else {
             *m = 0;
          }
           }
        }
     }
     break;
      case GL_NOTEQUAL:
     if (ctx->Depth.Mask) {
        /* Update Z buffer */
        for (i=0;i<n;i++,zptr++,m++) {
           if (*m) {
          if (z[i] != *zptr) {
             *zptr = z[i];
             passed++;
          }
          else {
             *m = 0;
          }
           }
        }
     }
     else {
        /* Don't update Z buffer */
        for (i=0;i<n;i++,zptr++,m++) {
           if (*m) {
          if (z[i] != *zptr) {
             /* pass */
             passed++;
          }
          else {
             *m = 0;
          }
           }
        }
     }
     break;
      case GL_EQUAL:
     if (ctx->Depth.Mask) {
        /* Update Z buffer */
        for (i=0;i<n;i++,zptr++,m++) {
           if (*m) {
          if (z[i] == *zptr) {
             *zptr = z[i];
             passed++;
          }
          else {
             *m =0;
          }
           }
        }
     }
     else {
        /* Don't update Z buffer */
        for (i=0;i<n;i++,zptr++,m++) {
           if (*m) {
          if (z[i] == *zptr) {
             /* pass */
             passed++;
          }
          else {
             *m =0;
          }
           }
        }
     }
     break;
      case GL_ALWAYS:
     if (ctx->Depth.Mask) {
        /* Update Z buffer */
        for (i=0;i<n;i++,zptr++,m++) {
           if (*m) {
          *zptr = z[i];
          passed++;
           }
        }
     }
     else {
        /* Don't update Z buffer or mask */
        passed = n;
     }
     break;
      case GL_NEVER:
     for (i=0;i<n;i++) {
        mask[i] = 0;
     }
     break;
      default:
         gl_problem(ctx, "Bad depth func in gl_depth_test_span_generic");
   } /*switch*/
 
   return passed;
}

Referenced by gl_update_state().

gl_depth_test_span_greater()

GLuint gl_depth_test_span_greater	(	GLcontext *	ctx,
		GLuint	n,
		GLint	x,
		GLint	y,
		const GLdepth	z[],
		GLubyte	mask[]
	)

Definition at line 447 of file depth.c.

{
   GLdepth *zptr = Z_ADDRESS( ctx, x, y );
   GLuint i;
   GLuint passed = 0;
 
   for (i=0; i<n; i++) {
      if (mask[i]) {
         if (z[i] > zptr[i]) {
            /* pass */
            zptr[i] = z[i];
            passed++;
         }
         else {
            /* fail */
            mask[i] = 0;
         }
      }
   }
   return passed;
}

Referenced by gl_update_state().

gl_depth_test_span_less()

GLuint gl_depth_test_span_less	(	GLcontext *	ctx,
		GLuint	n,
		GLint	x,
		GLint	y,
		const GLdepth	z[],
		GLubyte	mask[]
	)

Definition at line 419 of file depth.c.

{
   GLdepth *zptr = Z_ADDRESS( ctx, x, y );
   GLuint i;
   GLuint passed = 0;
 
   for (i=0; i<n; i++) {
      if (mask[i]) {
         if (z[i] < zptr[i]) {
            /* pass */
            zptr[i] = z[i];
            passed++;
         }
         else {
            /* fail */
            mask[i] = 0;
         }
      }
   }
   return passed;
}

Referenced by gl_update_state().

gl_DepthFunc()

void gl_DepthFunc	(	GLcontext *	ctx,
		GLenum	func
	)

Definition at line 98 of file depth.c.

{
   if (INSIDE_BEGIN_END(ctx)) {
      gl_error( ctx, GL_INVALID_OPERATION, "glDepthFunc" );
      return;
   }
 
   switch (func) {
      case GL_NEVER:
      case GL_LESS:    /* (default) pass if incoming z < stored z */
      case GL_GEQUAL:
      case GL_LEQUAL:
      case GL_GREATER:
      case GL_NOTEQUAL:
      case GL_EQUAL:
      case GL_ALWAYS:
         ctx->Depth.Func = func;
         ctx->NewState |= NEW_RASTER_OPS;
         break;
      default:
         gl_error( ctx, GL_INVALID_ENUM, "glDepth.Func" );
   }
}

Referenced by execute_list(), and init_exec_pointers().

gl_DepthMask()

void gl_DepthMask	(	GLcontext *	ctx,
		GLboolean	flag
	)

Definition at line 124 of file depth.c.

{
   if (INSIDE_BEGIN_END(ctx)) {
      gl_error( ctx, GL_INVALID_OPERATION, "glDepthMask" );
      return;
   }
 
   /*
    * GL_TRUE indicates depth buffer writing is enabled (default)
    * GL_FALSE indicates depth buffer writing is disabled
    */
   ctx->Depth.Mask = flag;
   ctx->NewState |= NEW_RASTER_OPS;
}

Referenced by execute_list(), and init_exec_pointers().

gl_DepthRange()

void gl_DepthRange	(	GLcontext *	ctx,
		GLclampd	nearval,
		GLclampd	farval
	)

Definition at line 141 of file depth.c.

{
   /*
    * nearval - specifies mapping of the near clipping plane to window
    *   coordinates, default is 0
    * farval - specifies mapping of the far clipping plane to window
    *   coordinates, default is 1
    *
    * After clipping and div by w, z coords are in -1.0 to 1.0,
    * corresponding to near and far clipping planes.  glDepthRange
    * specifies a linear mapping of the normalized z coords in
    * this range to window z coords.
    */
 
   GLfloat n, f;
 
   if (INSIDE_BEGIN_END(ctx)) {
      gl_error( ctx, GL_INVALID_OPERATION, "glDepthRange" );
      return;
   }
 
   n = (GLfloat) CLAMP( nearval, 0.0, 1.0 );
   f = (GLfloat) CLAMP( farval, 0.0, 1.0 );
 
   ctx->Viewport.Near = n;
   ctx->Viewport.Far = f;
   ctx->Viewport.Sz = DEPTH_SCALE * ((f - n) / 2.0);
   ctx->Viewport.Tz = DEPTH_SCALE * ((f - n) / 2.0 + n);
}

Referenced by execute_list(), and init_exec_pointers().

gl_read_depth_span_float()

void gl_read_depth_span_float	(	GLcontext *	ctx,
		GLuint	n,
		GLint	x,
		GLint	y,
		GLfloat	depth[]
	)

Definition at line 789 of file depth.c.

{
   GLdepth *zptr;
   GLfloat scale;
   GLuint i;
 
   scale = 1.0F / DEPTH_SCALE;
 
   if (ctx->Buffer->Depth) {
      zptr = Z_ADDRESS( ctx, x, y );
      for (i=0;i<n;i++) {
     depth[i] = (GLfloat) zptr[i] * scale;
      }
   }
   else {
      for (i=0;i<n;i++) {
     depth[i] = 0.0F;
      }
   }
}

Referenced by gl_update_state().

gl_read_depth_span_int()

void gl_read_depth_span_int	(	GLcontext *	ctx,
		GLuint	n,
		GLint	x,
		GLint	y,
		GLdepth	depth[]
	)

Definition at line 820 of file depth.c.

{
   if (ctx->Buffer->Depth) {
      GLdepth *zptr = Z_ADDRESS( ctx, x, y );
      MEMCPY( depth, zptr, n * sizeof(GLdepth) );
   }
   else {
      GLuint i;
      for (i=0;i<n;i++) {
     depth[i] = 0.0;
      }
   }
}

Referenced by gl_update_state().