This is vbrender.c in view mode; [Download] [Up]
/* $Id: vbrender.c,v 1.11 1997/05/28 03:26:49 brianp Exp $ */
/*
* Mesa 3-D graphics library
* Version: 2.3
* Copyright (C) 1995-1997 Brian Paul
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/*
* $Log: vbrender.c,v $
* Revision 1.11 1997/05/28 03:26:49 brianp
* added precompiled header (PCH) support
*
* Revision 1.10 1997/05/16 02:09:26 brianp
* clipped GL_TRIANGLE_STRIP triangles sometimes got wrong provoking vertex
*
* Revision 1.9 1997/04/30 02:20:00 brianp
* fixed a line clipping bug in GL_LINE_LOOPs
*
* Revision 1.8 1997/04/29 01:31:07 brianp
* added RasterSetup() function to device driver
*
* Revision 1.7 1997/04/24 00:30:17 brianp
* optimized glTexCoord2() code
*
* Revision 1.6 1997/04/20 19:47:06 brianp
* fixed an error message, added a comment
*
* Revision 1.5 1997/04/20 15:59:30 brianp
* removed VERTEX2_BIT stuff
*
* Revision 1.4 1997/04/20 15:27:34 brianp
* removed odd_flag from all polygon rendering functions
*
* Revision 1.3 1997/04/12 12:26:06 brianp
* now directly call ctx->Driver.Points/Line/Triangle/QuadFunc
*
* Revision 1.2 1997/04/07 03:01:11 brianp
* optimized vertex[234] code
*
* Revision 1.1 1997/04/02 03:14:14 brianp
* Initial revision
*
*/
/*
* Render points, lines, and polygons. The only entry point to this
* file is the gl_render_vb() function. This function is called after
* the vertex buffer has filled up or glEnd() has been called.
*
* This file basically only makes calls to the clipping functions and
* the point, line and triangle rasterizers via the function pointers.
* context->Driver.PointsFunc()
* context->Driver.LineFunc()
* context->Driver.TriangleFunc()
*/
#ifdef PCH
#include "all.h"
#else
#include "clip.h"
#include "context.h"
#include "macros.h"
#include "matrix.h"
#include "pb.h"
#include "types.h"
#include "vb.h"
#include "vbrender.h"
#include "xform.h"
#endif
/*
* This file implements rendering of points, lines and polygons defined by
* vertices in the vertex buffer.
*/
#ifdef PROFILE
# define START_PROFILE \
{ \
GLdouble t0 = gl_time();
# define END_PROFILE( TIMER, COUNTER, INCR ) \
TIMER += (gl_time() - t0); \
COUNTER += INCR; \
}
#else
# define START_PROFILE
# define END_PROFILE( TIMER, COUNTER, INCR )
#endif
/*
* Render a line segment from VB[v1] to VB[v2] when either one or both
* endpoints must be clipped.
*/
static void render_clipped_line( GLcontext *ctx, GLuint v1, GLuint v2 )
{
GLfloat d;
GLfloat ndc_x, ndc_y, ndc_z;
GLuint provoking_vertex;
struct vertex_buffer *VB = ctx->VB;
/* which vertex dictates the color when flat shading: */
provoking_vertex = v2;
/*
* Clipping may introduce new vertices. New vertices will be stored
* in the vertex buffer arrays starting with location VB->Free. After
* we've rendered the line, these extra vertices can be overwritten.
*/
VB->Free = VB_MAX;
/* Clip against user clipping planes */
if (ctx->Transform.AnyClip) {
GLuint orig_v1 = v1, orig_v2 = v2;
if (gl_userclip_line( ctx, &v1, &v2 )==0)
return;
/* Apply projection matrix: clip = Proj * eye */
if (v1!=orig_v1) {
TRANSFORM_POINT( VB->Clip[v1], ctx->ProjectionMatrix, VB->Eye[v1] );
}
if (v2!=orig_v2) {
TRANSFORM_POINT( VB->Clip[v2], ctx->ProjectionMatrix, VB->Eye[v2] );
}
}
/* Clip against view volume */
if (gl_viewclip_line( ctx, &v1, &v2 )==0)
return;
/* Transform from clip coords to ndc: ndc = clip / W */
ASSERT( VB->Clip[v1][3] != 0.0 );
d = 1.0F / VB->Clip[v1][3];
ndc_x = VB->Clip[v1][0] * d;
ndc_y = VB->Clip[v1][1] * d;
ndc_z = VB->Clip[v1][2] * d;
/* Map ndc coord to window coords. */
VB->Win[v1][0] = ndc_x * ctx->Viewport.Sx + ctx->Viewport.Tx;
VB->Win[v1][1] = ndc_y * ctx->Viewport.Sy + ctx->Viewport.Ty;
VB->Win[v1][2] = ndc_z * ctx->Viewport.Sz + ctx->Viewport.Tz;
/* Transform from clip coords to ndc: ndc = clip / W */
ASSERT( VB->Clip[v2][3] != 0.0 );
d = 1.0F / VB->Clip[v2][3];
ndc_x = VB->Clip[v2][0] * d;
ndc_y = VB->Clip[v2][1] * d;
ndc_z = VB->Clip[v2][2] * d;
/* Map ndc coord to window coords. */
VB->Win[v2][0] = ndc_x * ctx->Viewport.Sx + ctx->Viewport.Tx;
VB->Win[v2][1] = ndc_y * ctx->Viewport.Sy + ctx->Viewport.Ty;
VB->Win[v2][2] = ndc_z * ctx->Viewport.Sz + ctx->Viewport.Tz;
if (ctx->Driver.RasterSetup) {
/* Device driver rasterization setup */
(*ctx->Driver.RasterSetup)( ctx, v1, v1+1 );
(*ctx->Driver.RasterSetup)( ctx, v2, v2+1 );
}
START_PROFILE
(*ctx->Driver.LineFunc)( ctx, v1, v2, provoking_vertex );
END_PROFILE( ctx->LineTime, ctx->LineCount, 1 )
}
/*
* Compute Z offsets for a polygon with plane defined by (A,B,C,D)
* D is not needed.
*/
static void offset_polygon( GLcontext *ctx, GLfloat a, GLfloat b, GLfloat c )
{
GLfloat ac, bc, m;
GLfloat offset;
if (c<0.001F && c>-0.001F) {
/* to prevent underflow problems */
offset = 0.0F;
}
else {
ac = a / c;
bc = b / c;
if (ac<0.0F) ac = -ac;
if (bc<0.0F) bc = -bc;
m = MAX2( ac, bc );
/* m = sqrt( ac*ac + bc*bc ); */
offset = m * ctx->Polygon.OffsetFactor + ctx->Polygon.OffsetUnits;
}
ctx->PointZoffset = ctx->Polygon.OffsetPoint ? offset : 0.0F;
ctx->LineZoffset = ctx->Polygon.OffsetLine ? offset : 0.0F;
ctx->PolygonZoffset = ctx->Polygon.OffsetFill ? offset : 0.0F;
}
/*
* When glPolygonMode() is used to specify that the front/back rendering
* mode for polygons is not GL_FILL we end up calling this function.
*/
static void unfilled_polygon( GLcontext *ctx,
GLuint n, GLuint vlist[],
GLuint pv, GLuint facing )
{
GLenum mode = facing ? ctx->Polygon.BackMode : ctx->Polygon.FrontMode;
struct vertex_buffer *VB = ctx->VB;
if (mode==GL_POINT) {
GLint i, j;
GLboolean edge;
if ( ctx->Primitive==GL_TRIANGLES
|| ctx->Primitive==GL_QUADS
|| ctx->Primitive==GL_POLYGON) {
edge = GL_FALSE;
}
else {
edge = GL_TRUE;
}
for (i=0;i<n;i++) {
j = vlist[i];
if (edge || VB->Edgeflag[j]) {
(*ctx->Driver.PointsFunc)( ctx, j, j );
}
}
}
else if (mode==GL_LINE) {
GLuint i, j0, j1;
GLboolean edge;
ctx->StippleCounter = 0;
if ( ctx->Primitive==GL_TRIANGLES
|| ctx->Primitive==GL_QUADS
|| ctx->Primitive==GL_POLYGON) {
edge = GL_FALSE;
}
else {
edge = GL_TRUE;
}
/* draw the edges */
for (i=0;i<n;i++) {
j0 = (i==0) ? vlist[n-1] : vlist[i-1];
j1 = vlist[i];
if (edge || VB->Edgeflag[j0]) {
START_PROFILE
(*ctx->Driver.LineFunc)( ctx, j0, j1, pv );
END_PROFILE( ctx->LineTime, ctx->LineCount, 1 )
}
}
}
else {
/* Fill the polygon */
GLuint j0, i;
j0 = vlist[0];
for (i=2;i<n;i++) {
START_PROFILE
(*ctx->Driver.TriangleFunc)( ctx, j0, vlist[i-1], vlist[i], pv );
END_PROFILE( ctx->PolygonTime, ctx->PolygonCount, 1 )
}
}
}
/*
* Compute signed area of the n-sided polgyon specified by vertices vb->Win[]
* and vertex list vlist[].
* A clockwise polygon will return a negative area.
* A counter-clockwise polygon will return a positive area.
*/
static GLfloat polygon_area( const struct vertex_buffer *vb,
GLuint n, const GLuint vlist[] )
{
GLfloat area = 0.0F;
GLint i;
for (i=0;i<n;i++) {
/* area = sum of trapezoids */
GLuint j0 = vlist[i];
GLuint j1 = vlist[(i+1)%n];
GLfloat x0 = vb->Win[j0][0];
GLfloat y0 = vb->Win[j0][1];
GLfloat x1 = vb->Win[j1][0];
GLfloat y1 = vb->Win[j1][1];
GLfloat trapArea = (x0-x1)*(y0+y1); /* Note: no divide by two here! */
area += trapArea;
}
return area * 0.5F; /* divide by two now! */
}
/*
* Render a polygon in which doesn't have to be clipped.
* Input: n - number of vertices
* vlist - list of vertices in the polygon.
*/
static void render_polygon( GLcontext *ctx, GLuint n, GLuint vlist[] )
{
struct vertex_buffer *VB = ctx->VB;
GLuint pv;
/* which vertex dictates the color when flat shading: */
pv = (ctx->Primitive==GL_POLYGON) ? vlist[0] : vlist[n-1];
/* Compute orientation of polygon, do cull test, offset, etc */
{
GLuint facing; /* 0=front, 1=back */
GLfloat area = polygon_area( VB, n, vlist );
if (area==0.0F) {
/* polygon has zero area, don't draw it */
return;
}
facing = (area<0.0F) ^ (ctx->Polygon.FrontFace==GL_CW);
if ((facing+1) & ctx->Polygon.CullBits) {
return; /* culled */
}
if (ctx->Polygon.OffsetAny) {
/* compute plane equation of polygon, apply offset */
GLuint j0 = vlist[0];
GLuint j1 = vlist[1];
GLuint j2 = vlist[2];
GLuint j3 = vlist[ (n==3) ? 0 : 3 ];
GLfloat ex = VB->Win[j1][0] - VB->Win[j3][0];
GLfloat ey = VB->Win[j1][1] - VB->Win[j3][1];
GLfloat ez = VB->Win[j1][2] - VB->Win[j3][2];
GLfloat fx = VB->Win[j2][0] - VB->Win[j0][0];
GLfloat fy = VB->Win[j2][1] - VB->Win[j0][1];
GLfloat fz = VB->Win[j2][2] - VB->Win[j0][2];
GLfloat a = ey*fz-ez*fy;
GLfloat b = ez*fx-ex*fz;
GLfloat c = ex*fy-ey*fx;
offset_polygon( ctx, a, b, c );
}
if (ctx->Light.Model.TwoSide) {
if (facing==1 && ctx->Light.Enabled) {
/* use back color or index */
VB->Color = VB->Bcolor;
VB->Index = VB->Bindex;
}
else {
/* use front color or index */
VB->Color = VB->Fcolor;
VB->Index = VB->Findex;
}
}
/* Render the polygon! */
if (ctx->Polygon.Unfilled) {
unfilled_polygon( ctx, n, vlist, pv, facing );
}
else {
/* Draw filled polygon as a triangle fan */
GLint i;
GLuint j0 = vlist[0];
for (i=2;i<n;i++) {
START_PROFILE
(*ctx->Driver.TriangleFunc)( ctx, j0, vlist[i-1], vlist[i], pv );
END_PROFILE( ctx->PolygonTime, ctx->PolygonCount, 1 )
}
}
}
}
/*
* Render a polygon in which at least one vertex has to be clipped.
* Input: n - number of vertices
* vlist - list of vertices in the polygon.
* CCW order = front facing.
*/
static void render_clipped_polygon( GLcontext *ctx, GLuint n, GLuint vlist[] )
{
GLuint pv;
struct vertex_buffer *VB = ctx->VB;
GLfloat (*win)[3] = VB->Win;
/* which vertex dictates the color when flat shading: */
pv = (ctx->Primitive==GL_POLYGON) ? vlist[0] : vlist[n-1];
/*
* Clipping may introduce new vertices. New vertices will be stored
* in the vertex buffer arrays starting with location VB->Free. After
* we've rendered the polygon, these extra vertices can be overwritten.
*/
VB->Free = VB_MAX;
/* Clip against user clipping planes in eye coord space. */
if (ctx->Transform.AnyClip) {
GLfloat *proj = ctx->ProjectionMatrix;
GLuint i;
n = gl_userclip_polygon( ctx, n, vlist );
if (n<3)
return;
/* Transform vertices from eye to clip coordinates: clip = Proj * eye */
for (i=0;i<n;i++) {
GLuint j = vlist[i];
TRANSFORM_POINT( VB->Clip[j], proj, VB->Eye[j] );
}
}
/* Clip against view volume in clip coord space */
n = gl_viewclip_polygon( ctx, n, vlist );
if (n<3)
return;
/* Transform vertices from clip to ndc to window coords. */
/* ndc = clip / W window = viewport_mapping(ndc) */
/* Note that window Z values are scaled to the range of integer */
/* depth buffer values. */
{
GLfloat sx = ctx->Viewport.Sx;
GLfloat tx = ctx->Viewport.Tx;
GLfloat sy = ctx->Viewport.Sy;
GLfloat ty = ctx->Viewport.Ty;
GLfloat sz = ctx->Viewport.Sz;
GLfloat tz = ctx->Viewport.Tz;
GLuint i;
for (i=0;i<n;i++) {
GLuint j = vlist[i];
GLfloat d;
ASSERT( VB->Clip[j][3] != 0.0 );
d = 1.0F / VB->Clip[j][3];
win[j][0] = VB->Clip[j][0] * d * sx + tx;
win[j][1] = VB->Clip[j][1] * d * sy + ty;
win[j][2] = VB->Clip[j][2] * d * sz + tz;
}
if (ctx->Driver.RasterSetup) {
/* Device driver rasterization setup */
for (i=0;i<n;i++) {
GLuint j = vlist[i];
(*ctx->Driver.RasterSetup)( ctx, j, j+1 );
}
}
}
/* Compute orientation of polygon, do cull test, offset, etc */
{
GLuint facing; /* 0=front, 1=back */
GLfloat area = polygon_area( VB, n, vlist );
if (area==0.0F) {
/* polygon has zero area, don't draw it */
return;
}
facing = (area<0.0F) ^ (ctx->Polygon.FrontFace==GL_CW);
if ((facing+1) & ctx->Polygon.CullBits) {
return; /* culled */
}
if (ctx->Polygon.OffsetAny) {
/* compute plane equation of polygon, apply offset */
GLuint j0 = vlist[0];
GLuint j1 = vlist[1];
GLuint j2 = vlist[2];
GLuint j3 = vlist[ (n==3) ? 0 : 3 ];
GLfloat ex = win[j1][0] - win[j3][0];
GLfloat ey = win[j1][1] - win[j3][1];
GLfloat ez = win[j1][2] - win[j3][2];
GLfloat fx = win[j2][0] - win[j0][0];
GLfloat fy = win[j2][1] - win[j0][1];
GLfloat fz = win[j2][2] - win[j0][2];
GLfloat a = ey*fz-ez*fy;
GLfloat b = ez*fx-ex*fz;
GLfloat c = ex*fy-ey*fx;
offset_polygon( ctx, a, b, c );
}
if (ctx->Light.Model.TwoSide) {
if (facing==1 && ctx->Light.Enabled) {
/* use back color or index */
VB->Color = VB->Bcolor;
VB->Index = VB->Bindex;
}
else {
/* use front color or index */
VB->Color = VB->Fcolor;
VB->Index = VB->Findex;
}
}
/* Render the polygon! */
if (ctx->Polygon.Unfilled) {
unfilled_polygon( ctx, n, vlist, pv, facing );
}
else {
/* Draw filled polygon as a triangle fan */
GLint i;
GLuint j0 = vlist[0];
for (i=2;i<n;i++) {
START_PROFILE
(*ctx->Driver.TriangleFunc)( ctx, j0, vlist[i-1], vlist[i], pv );
END_PROFILE( ctx->PolygonTime, ctx->PolygonCount, 1 )
}
}
}
}
/*
* Render an un-clipped triangle.
* v0, v1, v2 - vertex indexes. CCW order = front facing
* pv - provoking vertex
*/
static void render_triangle( GLcontext *ctx,
GLuint v0, GLuint v1, GLuint v2, GLuint pv )
{
struct vertex_buffer *VB = ctx->VB;
GLfloat ex, ey, fx, fy, c;
GLuint facing; /* 0=front, 1=back */
GLfloat (*win)[3] = VB->Win;
/* Compute orientation of triangle */
ex = win[v1][0] - win[v0][0];
ey = win[v1][1] - win[v0][1];
fx = win[v2][0] - win[v0][0];
fy = win[v2][1] - win[v0][1];
c = ex*fy-ey*fx;
if (c==0.0F) {
/* polygon is perpindicular to view plane, don't draw it */
return;
}
facing = (c<0.0F) ^ (ctx->Polygon.FrontFace==GL_CW);
if ((facing+1) & ctx->Polygon.CullBits) {
return; /* culled */
}
if (ctx->Polygon.OffsetAny) {
/* finish computing plane equation of polygon, compute offset */
GLfloat fz = win[v2][2] - win[v0][2];
GLfloat ez = win[v1][2] - win[v0][2];
GLfloat a = ey*fz-ez*fy;
GLfloat b = ez*fx-ex*fz;
offset_polygon( ctx, a, b, c );
}
if (ctx->Light.Model.TwoSide) {
if (facing==1 && ctx->Light.Enabled) {
/* use back color or index */
VB->Color = VB->Bcolor;
VB->Index = VB->Bindex;
}
else {
/* use front color or index */
VB->Color = VB->Fcolor;
VB->Index = VB->Findex;
}
}
if (ctx->Polygon.Unfilled) {
GLuint vlist[3];
vlist[0] = v0;
vlist[1] = v1;
vlist[2] = v2;
unfilled_polygon( ctx, 3, vlist, pv, facing );
}
else {
START_PROFILE
(*ctx->Driver.TriangleFunc)( ctx, v0, v1, v2, pv );
END_PROFILE( ctx->PolygonTime, ctx->PolygonCount, 1 )
}
}
/*
* Render an un-clipped quadrilateral.
* v0, v1, v2, v3 : CCW order = front facing
* pv - provoking vertex
*/
static void render_quad( GLcontext *ctx, GLuint v0, GLuint v1,
GLuint v2, GLuint v3, GLuint pv )
{
struct vertex_buffer *VB = ctx->VB;
GLfloat ex, ey, fx, fy, c;
GLuint facing; /* 0=front, 1=back */
GLfloat (*win)[3] = VB->Win;
/* Compute polygon orientation */
ex = win[v2][0] - win[v0][0];
ey = win[v2][1] - win[v0][1];
fx = win[v3][0] - win[v1][0];
fy = win[v3][1] - win[v1][1];
c = ex*fy-ey*fx;
if (c==0.0F) {
/* polygon is perpindicular to view plane, don't draw it */
return;
}
facing = (c<0.0F) ^ (ctx->Polygon.FrontFace==GL_CW);
if ((facing+1) & ctx->Polygon.CullBits) {
return; /* culled */
}
if (ctx->Polygon.OffsetAny) {
/* finish computing plane equation of polygon, compute offset */
GLfloat ez = win[v2][2] - win[v0][2];
GLfloat fz = win[v3][2] - win[v1][2];
GLfloat a = ey*fz-ez*fy;
GLfloat b = ez*fx-ex*fz;
offset_polygon( ctx, a, b, c );
}
if (ctx->Light.Model.TwoSide) {
if (facing==1 && ctx->Light.Enabled) {
/* use back color or index */
VB->Color = VB->Bcolor;
VB->Index = VB->Bindex;
}
else {
/* use front color or index */
VB->Color = VB->Fcolor;
VB->Index = VB->Findex;
}
}
/* Render the quad! */
if (ctx->Polygon.Unfilled) {
GLuint vlist[4];
vlist[0] = v0;
vlist[1] = v1;
vlist[2] = v2;
vlist[3] = v3;
unfilled_polygon( ctx, 4, vlist, pv, facing );
}
else {
START_PROFILE
(*ctx->Driver.QuadFunc)( ctx, v0, v1, v2, v3, pv );
END_PROFILE( ctx->PolygonTime, ctx->PolygonCount, 2 )
}
}
/*
* When the vertex buffer is full, we transform/render it. Sometimes we
* have to copy the last vertex (or two) to the front of the vertex list
* to "continue" the primitive. For example: line or triangle strips.
* This function is a helper for that.
*/
static void copy_vertex( struct vertex_buffer *vb, GLuint dst, GLuint src )
{
COPY_4V( vb->Clip[dst], vb->Clip[src] );
COPY_4V( vb->Eye[dst], vb->Eye[src] );
COPY_3V( vb->Win[dst], vb->Win[src] );
COPY_4V( vb->Fcolor[dst], vb->Fcolor[src] );
COPY_4V( vb->Bcolor[dst], vb->Bcolor[src] );
COPY_4V( vb->TexCoord[dst], vb->TexCoord[src] );
vb->Findex[dst] = vb->Findex[src];
vb->Bindex[dst] = vb->Bindex[src];
vb->Edgeflag[dst] = vb->Edgeflag[src];
vb->ClipMask[dst] = vb->ClipMask[src];
}
/*
* Either the vertex buffer is full (VB->Count==VB_MAX) or glEnd() has been
* called. Render the primitives defined by the vertices and reset the
* buffer.
*
* This function won't be called if the device driver implements a
* RenderVB() function. If the device driver renders the vertex buffer
* then the driver must also call gl_reset_vb()!
*
* Input: allDone - GL_TRUE = caller is glEnd()
* GL_FALSE = calling because buffer is full.
*/
void gl_render_vb( GLcontext *ctx, GLboolean allDone )
{
struct vertex_buffer *VB = ctx->VB;
GLuint vlist[VB_SIZE];
switch (ctx->Primitive) {
case GL_POINTS:
START_PROFILE
(*ctx->Driver.PointsFunc)( ctx, 0, VB->Count-1 );
END_PROFILE( ctx->PointTime, ctx->PointCount, VB->Count )
break;
case GL_LINES:
if (VB->ClipOrMask) {
GLuint i;
for (i=1;i<VB->Count;i+=2) {
if (VB->ClipMask[i-1] | VB->ClipMask[i]) {
render_clipped_line( ctx, i-1, i );
}
else {
START_PROFILE
(*ctx->Driver.LineFunc)( ctx, i-1, i, i );
END_PROFILE( ctx->LineTime, ctx->LineCount, 1 )
}
ctx->StippleCounter = 0;
}
}
else {
GLuint i;
for (i=1;i<VB->Count;i+=2) {
START_PROFILE
(*ctx->Driver.LineFunc)( ctx, i-1, i, i );
END_PROFILE( ctx->LineTime, ctx->LineCount, 1 )
ctx->StippleCounter = 0;
}
}
break;
case GL_LINE_STRIP:
if (VB->ClipOrMask) {
GLuint i;
for (i=1;i<VB->Count;i++) {
if (VB->ClipMask[i-1] | VB->ClipMask[i]) {
render_clipped_line( ctx, i-1, i );
}
else {
START_PROFILE
(*ctx->Driver.LineFunc)( ctx, i-1, i, i );
END_PROFILE( ctx->LineTime, ctx->LineCount, 1 )
}
}
}
else {
/* no clipping needed */
GLuint i;
for (i=1;i<VB->Count;i++) {
START_PROFILE
(*ctx->Driver.LineFunc)( ctx, i-1, i, i );
END_PROFILE( ctx->LineTime, ctx->LineCount, 1 )
}
}
break;
case GL_LINE_LOOP:
{
GLuint i;
if (VB->Start==0) {
i = 1; /* start at 0th vertex */
}
else {
i = 2; /* skip first vertex, we're saving it until glEnd */
}
while (i<VB->Count) {
if (VB->ClipMask[i-1] | VB->ClipMask[i]) {
render_clipped_line( ctx, i-1, i );
}
else {
START_PROFILE
(*ctx->Driver.LineFunc)( ctx, i-1, i, i );
END_PROFILE( ctx->LineTime, ctx->LineCount, 1 )
}
i++;
}
}
break;
case GL_TRIANGLES:
if (VB->ClipOrMask) {
GLuint i;
for (i=2;i<VB->Count;i+=3) {
if (VB->ClipMask[i-2] | VB->ClipMask[i-1] | VB->ClipMask[i]) {
vlist[0] = i-2;
vlist[1] = i-1;
vlist[2] = i-0;
render_clipped_polygon( ctx, 3, vlist );
}
else {
if (ctx->DirectTriangles) {
START_PROFILE
(*ctx->Driver.TriangleFunc)( ctx, i-2, i-1, i, i );
END_PROFILE( ctx->PolygonTime, ctx->PolygonCount, 1 )
}
else {
render_triangle( ctx, i-2, i-1, i, i );
}
}
}
}
else {
/* no clipping needed */
GLuint i;
if (ctx->DirectTriangles) {
for (i=2;i<VB->Count;i+=3) {
START_PROFILE
(*ctx->Driver.TriangleFunc)( ctx, i-2, i-1, i, i );
END_PROFILE( ctx->PolygonTime, ctx->PolygonCount, 1 )
}
}
else {
for (i=2;i<VB->Count;i+=3) {
render_triangle( ctx, i-2, i-1, i, i );
}
}
}
break;
case GL_TRIANGLE_STRIP:
if (VB->ClipOrMask) {
GLuint i;
for (i=2;i<VB->Count;i++) {
if (VB->ClipMask[i-2] | VB->ClipMask[i-1] | VB->ClipMask[i]) {
if (i&1) {
/* reverse vertex order */
vlist[0] = i-1;
vlist[1] = i-2;
vlist[2] = i-0;
render_clipped_polygon( ctx, 3, vlist );
}
else {
vlist[0] = i-2;
vlist[1] = i-1;
vlist[2] = i-0;
render_clipped_polygon( ctx, 3, vlist );
}
}
else {
if (ctx->DirectTriangles) {
START_PROFILE
(*ctx->Driver.TriangleFunc)( ctx, i-2, i-1, i, i );
END_PROFILE( ctx->PolygonTime, ctx->PolygonCount, 1 )
}
else {
if (i&1)
render_triangle( ctx, i, i-1, i-2, i );
else
render_triangle( ctx, i-2, i-1, i, i );
}
}
}
}
else {
/* no vertices were clipped */
GLuint i;
if (ctx->DirectTriangles) {
for (i=2;i<VB->Count;i++) {
START_PROFILE
(*ctx->Driver.TriangleFunc)( ctx, i-2, i-1, i, i );
END_PROFILE( ctx->PolygonTime, ctx->PolygonCount, 1 )
}
}
else {
for (i=2;i<VB->Count;i++) {
if (i&1)
render_triangle( ctx, i, i-1, i-2, i );
else
render_triangle( ctx, i-2, i-1, i, i );
}
}
}
break;
case GL_TRIANGLE_FAN:
if (VB->ClipOrMask) {
GLuint i;
for (i=2;i<VB->Count;i++) {
if (VB->ClipMask[0] | VB->ClipMask[i-1] | VB->ClipMask[i]) {
vlist[0] = 0;
vlist[1] = i-1;
vlist[2] = i;
render_clipped_polygon( ctx, 3, vlist );
}
else {
if (ctx->DirectTriangles) {
START_PROFILE
(*ctx->Driver.TriangleFunc)( ctx, 0, i-1, i, i );
END_PROFILE( ctx->PolygonTime, ctx->PolygonCount, 1 )
}
else {
render_triangle( ctx, 0, i-1, i, i );
}
}
}
}
else {
/* no clipping needed */
GLuint i;
if (ctx->DirectTriangles) {
for (i=2;i<VB->Count;i++) {
START_PROFILE
(*ctx->Driver.TriangleFunc)( ctx, 0, i-1, i, i );
END_PROFILE( ctx->PolygonTime, ctx->PolygonCount, 1 )
}
}
else {
for (i=2;i<VB->Count;i++) {
render_triangle( ctx, 0, i-1, i, i );
}
}
}
break;
case GL_QUADS:
if (VB->ClipOrMask) {
GLuint i;
for (i=3;i<VB->Count;i+=4) {
if ( VB->ClipMask[i-3] | VB->ClipMask[i-2]
| VB->ClipMask[i-1] | VB->ClipMask[i]) {
vlist[0] = i-3;
vlist[1] = i-2;
vlist[2] = i-1;
vlist[3] = i-0;
render_clipped_polygon( ctx, 4, vlist );
}
else {
if (ctx->DirectTriangles) {
START_PROFILE
(*ctx->Driver.QuadFunc)( ctx, i-3, i-2, i-1, i, i );
END_PROFILE( ctx->PolygonTime, ctx->PolygonCount, 2 )
}
else {
render_quad( ctx, i-3, i-2, i-1, i, i );
}
}
}
}
else {
/* no vertices were clipped */
GLuint i;
if (ctx->DirectTriangles) {
for (i=3;i<VB->Count;i+=4) {
START_PROFILE
(*ctx->Driver.QuadFunc)( ctx, i-3, i-2, i-1, i, i );
END_PROFILE( ctx->PolygonTime, ctx->PolygonCount, 2 )
}
}
else {
for (i=3;i<VB->Count;i+=4) {
render_quad( ctx, i-3, i-2, i-1, i, i );
}
}
}
break;
case GL_QUAD_STRIP:
if (VB->ClipOrMask) {
GLuint i;
for (i=3;i<VB->Count;i+=2) {
if ( VB->ClipMask[i-2] | VB->ClipMask[i-3]
| VB->ClipMask[i-1] | VB->ClipMask[i]) {
vlist[0] = i-3;
vlist[1] = i-2;
vlist[2] = i-0;
vlist[3] = i-1;
render_clipped_polygon( ctx, 4, vlist );
}
else {
if (ctx->DirectTriangles) {
START_PROFILE
(*ctx->Driver.QuadFunc)( ctx, i-3, i-2, i, i-1, i );
END_PROFILE( ctx->PolygonTime, ctx->PolygonCount, 2 )
}
else {
render_quad( ctx, i-3, i-2, i, i-1, i );
}
}
}
}
else {
/* no clipping needed */
GLuint i;
if (ctx->DirectTriangles) {
for (i=3;i<VB->Count;i+=2) {
START_PROFILE
(*ctx->Driver.QuadFunc)( ctx, i-3, i-2, i, i-1, i );
END_PROFILE( ctx->PolygonTime, ctx->PolygonCount, 2 )
}
}
else {
for (i=3;i<VB->Count;i+=2) {
render_quad( ctx, i-3, i-2, i, i-1, i );
}
}
}
break;
case GL_POLYGON:
if (VB->Count>2) {
GLuint i;
for (i=0;i<VB->Count;i++) {
vlist[i] = i;
}
if (VB->ClipOrMask) {
render_clipped_polygon( ctx, VB->Count, vlist );
}
else {
render_polygon( ctx, VB->Count, vlist );
}
}
break;
default:
/* should never get here */
gl_problem( ctx, "invalid mode in gl_render_vb" );
}
gl_reset_vb( ctx, allDone );
}
#define CLIP_ALL_BITS 0x3f
/*
* After we've rendered the primitives in the vertex buffer we call
* this function to reset the vertex buffer. That is, we prepare it
* for the next batch of vertices.
* Input: ctx - the context
* allDone - GL_TRUE = glEnd() was called
* GL_FALSE = buffer was filled, more vertices to come
*/
void gl_reset_vb( GLcontext *ctx, GLboolean allDone )
{
struct vertex_buffer *VB = ctx->VB;
if (ctx->Primitive==GL_LINE_LOOP && allDone) {
/* special case */
if (VB->ClipMask[VB->Count-1] | VB->ClipMask[0]) {
render_clipped_line( ctx, VB->Count-1, 0 );
}
else {
START_PROFILE
(*ctx->Driver.LineFunc)( ctx, VB->Count-1, 0, 0 );
END_PROFILE( ctx->LineTime, ctx->LineCount, 1 )
}
}
if (VB->ClipOrMask) {
/* reset clip masks to zero */
MEMSET( VB->ClipMask + VB->Start, 0,
(VB->Count - VB->Start) * sizeof(VB->ClipMask[0]) );
}
if (!VB->MonoMaterial) {
/* reset material masks to zero */
MEMSET( VB->MaterialMask + VB->Start, 0,
(VB->Count - VB->Start) * sizeof(VB->MaterialMask[0]) );
}
if (VB->VertexSizeMask!=VERTEX3_BIT) {
/* reset object W coords to one */
GLint i, n;
GLfloat (*obj)[4] = VB->Obj + VB->Start;
n = VB->Count - VB->Start;
for (i=0; i<n; i++) {
obj[i][3] = 1.0F;
}
}
if (allDone) {
VB->MonoColor = GL_TRUE;
VB->VertexSizeMask = VERTEX3_BIT;
if (VB->TexCoordSize!=2) {
GLint i, n = VB->Count;
for (i=0;i<n;i++) {
VB->TexCoord[i][2] = 0.0F;
VB->TexCoord[i][3] = 1.0F;
}
}
if (ctx->Current.TexCoord[2]==0.0F && ctx->Current.TexCoord[3]==1.0F) {
VB->TexCoordSize = 2;
}
else {
VB->TexCoordSize = 4;
}
}
switch (ctx->Primitive) {
case GL_POINTS:
ASSERT(VB->Start==0);
VB->Count = 0;
VB->ClipOrMask = 0;
VB->ClipAndMask = CLIP_ALL_BITS;
VB->MonoMaterial = GL_TRUE;
VB->MonoNormal = GL_TRUE;
break;
case GL_LINES:
ASSERT(VB->Start==0);
VB->Count = 0;
VB->ClipOrMask = 0;
VB->ClipAndMask = CLIP_ALL_BITS;
VB->MonoMaterial = GL_TRUE;
VB->MonoNormal = GL_TRUE;
break;
case GL_LINE_STRIP:
if (allDone) {
VB->Count = 0;
VB->ClipOrMask = 0;
VB->ClipAndMask = CLIP_ALL_BITS;
VB->MonoMaterial = GL_TRUE;
VB->MonoNormal = GL_TRUE;
}
else {
copy_vertex( VB, 0, VB->Count-1 ); /* copy last vertex to front */
VB->Count = 1;
VB->ClipOrMask = VB->ClipMask[0];
VB->ClipAndMask = VB->ClipMask[0];
VB->MonoMaterial = VB->MaterialMask[0] ? GL_FALSE : GL_TRUE;
}
break;
case GL_LINE_LOOP:
if (allDone) {
VB->Count = 0;
VB->ClipOrMask = 0;
VB->ClipAndMask = CLIP_ALL_BITS;
VB->MonoMaterial = GL_TRUE;
VB->MonoNormal = GL_TRUE;
}
else {
ASSERT(VB->Count==VB_MAX);
/* recycle the vertex list */
copy_vertex( VB, 1, VB_MAX-1 );
VB->Count = 2;
VB->ClipOrMask = VB->ClipMask[0] | VB->ClipMask[1];
VB->ClipAndMask = VB->ClipMask[0] & VB->ClipMask[1];
VB->MonoMaterial = !(VB->MaterialMask[0] | VB->MaterialMask[1]);
}
break;
case GL_TRIANGLES:
ASSERT(VB->Start==0);
VB->Count = 0;
VB->ClipOrMask = 0;
VB->ClipAndMask = CLIP_ALL_BITS;
VB->MonoMaterial = GL_TRUE;
VB->MonoNormal = GL_TRUE;
break;
case GL_TRIANGLE_STRIP:
if (allDone) {
VB->Count = 0;
VB->ClipOrMask = 0;
VB->ClipAndMask = CLIP_ALL_BITS;
VB->MonoMaterial = GL_TRUE;
VB->MonoNormal = GL_TRUE;
}
else {
/* get ready for more vertices in this triangle strip */
copy_vertex( VB, 0, VB_MAX-2 );
copy_vertex( VB, 1, VB_MAX-1 );
VB->Count = 2;
VB->ClipOrMask = VB->ClipMask[0] | VB->ClipMask[1];
VB->ClipAndMask = VB->ClipMask[0] & VB->ClipMask[1];
VB->MonoMaterial = !(VB->MaterialMask[0] | VB->MaterialMask[1]);
}
break;
case GL_TRIANGLE_FAN:
if (allDone) {
VB->Count = 0;
VB->ClipOrMask = 0;
VB->ClipAndMask = CLIP_ALL_BITS;
VB->MonoMaterial = GL_TRUE;
VB->MonoNormal = GL_TRUE;
}
else {
/* get ready for more vertices in this triangle fan */
copy_vertex( VB, 1, VB_MAX-1 );
VB->Count = 2;
VB->ClipOrMask = VB->ClipMask[0] | VB->ClipMask[1];
VB->ClipAndMask = VB->ClipMask[0] & VB->ClipMask[1];
VB->MonoMaterial = !(VB->MaterialMask[0] | VB->MaterialMask[1]);
}
break;
case GL_QUADS:
ASSERT(VB->Start==0);
VB->Count = 0;
VB->ClipOrMask = 0;
VB->ClipAndMask = CLIP_ALL_BITS;
VB->MonoMaterial = GL_TRUE;
VB->MonoNormal = GL_TRUE;
break;
case GL_QUAD_STRIP:
if (allDone) {
VB->Count = 0;
VB->ClipOrMask = 0;
VB->ClipAndMask = CLIP_ALL_BITS;
VB->MonoMaterial = GL_TRUE;
VB->MonoNormal = GL_TRUE;
}
else {
/* get ready for more vertices in this quad strip */
copy_vertex( VB, 0, VB_MAX-2 );
copy_vertex( VB, 1, VB_MAX-1 );
VB->Count = 2;
VB->ClipOrMask = VB->ClipMask[0] | VB->ClipMask[1];
VB->ClipAndMask = VB->ClipMask[0] & VB->ClipMask[1];
VB->MonoMaterial = !(VB->MaterialMask[0] | VB->MaterialMask[1]);
}
break;
case GL_POLYGON:
if (allDone) {
VB->Count = 0;
VB->ClipOrMask = 0;
VB->ClipAndMask = CLIP_ALL_BITS;
VB->MonoMaterial = GL_TRUE;
VB->MonoNormal = GL_TRUE;
}
else {
/* get ready for more vertices just like a triangle fan */
copy_vertex( VB, 1, VB_MAX-1 );
VB->Count = 2;
VB->ClipOrMask = VB->ClipMask[0] | VB->ClipMask[1];
VB->ClipAndMask = VB->ClipMask[0] & VB->ClipMask[1];
VB->MonoMaterial = !(VB->MaterialMask[0] | VB->MaterialMask[1]);
}
break;
default:
/* should never get here */
gl_problem( ctx, "invalid mode in gl_reset_vb" );
}
/* In any case, Start = first vertex which hasn't been transformed yet */
VB->Start = VB->Count;
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.