GLboolean select_segment_in_viewscreen(const GLfloat *a, const GLfloat *b) {
/*
Return True is the segment is fully inside viewscreen
or cross the viewscreen
Viewscreen is (-1,-1)(+1,+1)
False if completly outside
*/
// Fast either point inside viewport
if (select_point_in_viewscreen(a)) return true;
if (select_point_in_viewscreen(b)) return true;
// Using Liang-Barsky algorithm
GLfloat vx, vy;
vx=b[0]-a[0];
vy=b[1]-a[1];
GLfloat p[4] = {-vx, vx, -vy, vy};
GLfloat q[4] = {a[0] + 1.0f, +1.0f - a[0], a[1] + 1.0f, +1.0f - a[1]};
GLfloat u1 = 0.0f;
GLfloat u2 = 1.0f;
for (int i=0; i<4; i++) {
if (p[i] == 0.0f) {
if (q[i]<0.0f)
return false;
} else {
GLfloat t =q[i] / p[i];
if (p[i]<0.0) {
if(t>u2) return false;
else if(u1<t)
u1 = t;
}
else if (p[i]>0.0) {
if(t<u1) return false;
else if (u2>t)
u2 = t;
}
}
}
return true;
}
void select_glDrawElements(const pointer_state_t* vtx, GLenum mode, GLuint count, GLenum type, GLvoid * indices) {
if (count == 0) return;
if (vtx->pointer == NULL) return;
GLushort *sind = (GLushort*)((type==GL_UNSIGNED_SHORT)?indices:NULL);
GLuint *iind = (GLuint*)((type==GL_UNSIGNED_INT)?indices:NULL);
GLsizei min, max;
if(sind)
getminmax_indices_us(sind, &max, &min, count);
else
getminmax_indices_ui(iind, &max, &min, count);
max++;
GLfloat *vert = copy_gl_array(vtx->pointer, vtx->type,
vtx->size, vtx->stride,
GL_FLOAT, 4, 0, max);
GLfloat zmin=1e10f, zmax=-10e6f;
int found = 0;
for (int i=min; i<max; i++) {
select_transform(vert+i*4);
ZMinMax(&glstate->selectbuf.zminoverall, &glstate->selectbuf.zmaxoverall, vert+i*4);
}
#define FOUND() { \
found = 1; \
glstate->selectbuf.hit = 1; \
}
if(sind) {
for (int i=0; i<count; i++) {
switch (mode) {
case GL_POINTS:
if (select_point_in_viewscreen(vert+sind[i]*4)) {
ZMinMax(&zmin, &zmax, vert+sind[i]*4);
FOUND();
}
break;
case GL_LINES:
if (i%2==1) {
if (select_segment_in_viewscreen(vert+sind[(i-1)]*4, vert+sind[i]*4)) {
ZMinMax(&zmin, &zmax, vert+sind[i-1]*4);
ZMinMax(&zmin, &zmax, vert+sind[i]*4);
FOUND();
}
}
break;
case GL_LINE_STRIP:
case GL_LINE_LOOP: //FIXME: the last "loop" segment is missing here
if (i>0) {
if (select_segment_in_viewscreen(vert+sind[(i-1)]*4, vert+sind[i]*4)) {
ZMinMax(&zmin, &zmax, vert+sind[i-1]*4);
ZMinMax(&zmin, &zmax, vert+sind[i]*4);
FOUND();
}
}
break;
case GL_TRIANGLES:
if (i%3==2) {
if (select_triangle_in_viewscreen(vert+sind[(i-2)]*4, vert+sind[(i-1)]*4, vert+sind[i]*4)) {
ZMinMax(&zmin, &zmax, vert+sind[i-2]*4);
ZMinMax(&zmin, &zmax, vert+sind[i-1]*4);
ZMinMax(&zmin, &zmax, vert+sind[i]*4);
FOUND();
}
}
break;
case GL_TRIANGLE_STRIP:
if (i>1) {
if (select_triangle_in_viewscreen(vert+sind[(i-2)]*4, vert+sind[(i-1)]*4, vert+sind[i]*4)) {
ZMinMax(&zmin, &zmax, vert+sind[i-2]*4);
ZMinMax(&zmin, &zmax, vert+sind[i-1]*4);
ZMinMax(&zmin, &zmax, vert+sind[i]*4);
FOUND();
}
}
break;
case GL_TRIANGLE_FAN:
if (i>1) {
if (select_triangle_in_viewscreen(vert+sind[0]*4, vert+sind[(i-1)]*4, vert+sind[i]*4))
ZMinMax(&zmin, &zmax, vert+sind[0]*4);
ZMinMax(&zmin, &zmax, vert+sind[i-1]*4);
ZMinMax(&zmin, &zmax, vert+sind[i]*4);
FOUND();
}
break;
default:
return; // Should never go there!
}
}
} else {
for (int i=0; i<count; i++) {
switch (mode) {
case GL_POINTS:
if (select_point_in_viewscreen(vert+iind[i]*4)) {
ZMinMax(&zmin, &zmax, vert+iind[i]*4);
FOUND();
}
break;
case GL_LINES:
if (i%2==1) {
if (select_segment_in_viewscreen(vert+iind[(i-1)]*4, vert+iind[i]*4)) {
ZMinMax(&zmin, &zmax, vert+iind[i-1]*4);
ZMinMax(&zmin, &zmax, vert+iind[i]*4);
FOUND();
}
}
break;
case GL_LINE_STRIP:
case GL_LINE_LOOP: //FIXME: the last "loop" segment is missing here
if (i>0) {
if (select_segment_in_viewscreen(vert+iind[(i-1)]*4, vert+iind[i]*4)) {
ZMinMax(&zmin, &zmax, vert+iind[i-1]*4);
ZMinMax(&zmin, &zmax, vert+iind[i]*4);
FOUND();
}
}
break;
case GL_TRIANGLES:
if (i%3==2) {
if (select_triangle_in_viewscreen(vert+iind[(i-2)]*4, vert+iind[(i-1)]*4, vert+iind[i]*4)) {
ZMinMax(&zmin, &zmax, vert+iind[i-2]*4);
ZMinMax(&zmin, &zmax, vert+iind[i-1]*4);
ZMinMax(&zmin, &zmax, vert+iind[i]*4);
FOUND();
}
}
break;
case GL_TRIANGLE_STRIP:
if (i>1) {
if (select_triangle_in_viewscreen(vert+iind[(i-2)]*4, vert+iind[(i-1)]*4, vert+iind[i]*4)) {
ZMinMax(&zmin, &zmax, vert+iind[i-2]*4);
ZMinMax(&zmin, &zmax, vert+iind[i-1]*4);
ZMinMax(&zmin, &zmax, vert+iind[i]*4);
FOUND();
}
}
break;
case GL_TRIANGLE_FAN:
if (i>1) {
if (select_triangle_in_viewscreen(vert+iind[0]*4, vert+iind[(i-1)]*4, vert+iind[i]*4))
ZMinMax(&zmin, &zmax, vert+iind[0]*4);
ZMinMax(&zmin, &zmax, vert+iind[i-1]*4);
ZMinMax(&zmin, &zmax, vert+iind[i]*4);
FOUND();
}
break;
default:
return; // Should never go there!
}
}
}
free(vert);
if(found) {
if (zmin<glstate->selectbuf.zmin) glstate->selectbuf.zmin=zmin;
if (zmax>glstate->selectbuf.zmax) glstate->selectbuf.zmax=zmax;
}
#undef FOUND
}
void select_glDrawArrays(const pointer_state_t* vtx, GLenum mode, GLuint first, GLuint count) {
if (count == 0) return;
if (vtx->pointer == NULL) return;
if (glstate->selectbuf.buffer == NULL) return;
GLfloat *vert = copy_gl_array(vtx->pointer, vtx->type,
vtx->size, vtx->stride,
GL_FLOAT, 4, 0, count+first);
GLfloat zmin=1e10f, zmax=-1e10f;
int found = 0;
#define FOUND() { \
found = 1; \
glstate->selectbuf.hit = 1; \
}
// transform the points
for (int i=first; i<count+first; i++) {
select_transform(vert+i*4);
ZMinMax(&glstate->selectbuf.zminoverall, &glstate->selectbuf.zmaxoverall, vert+i*4);
}
// intersect with screen now
GLfloat *vert2 = vert + first*4;
for (int i=0; i<count; i++) {
switch (mode) {
case GL_POINTS:
if (select_point_in_viewscreen(vert2+i*4)) {
ZMinMax(&zmin, &zmax, vert+i*4);
FOUND();
}
break;
case GL_LINES:
if (i%2==1) {
if (select_segment_in_viewscreen(vert2+(i-1)*4, vert2+i*4)) {
ZMinMax(&zmin, &zmax, vert+(i-1)*4);
ZMinMax(&zmin, &zmax, vert+i*4);
FOUND();
}
}
break;
case GL_LINE_STRIP:
case GL_LINE_LOOP: //FIXME: the last "loop" segment is missing here
if (i>0) {
if (select_segment_in_viewscreen(vert2+(i-1)*4, vert2+i*4)) {
ZMinMax(&zmin, &zmax, vert+(i-1)*4);
ZMinMax(&zmin, &zmax, vert+i*4);
FOUND();
}
}
break;
case GL_TRIANGLES:
if (i%3==2) {
if (select_triangle_in_viewscreen(vert2+(i-2)*4, vert2+(i-1)*4, vert2+i*4)) {
ZMinMax(&zmin, &zmax, vert+(i-2)*4);
ZMinMax(&zmin, &zmax, vert+(i-1)*4);
ZMinMax(&zmin, &zmax, vert+i*4);
FOUND();
}
}
break;
case GL_TRIANGLE_STRIP:
if (i>1) {
if (select_triangle_in_viewscreen(vert2+(i-2)*4, vert2+(i-1)*4, vert2+i*4)) {
ZMinMax(&zmin, &zmax, vert+(i-2)*4);
ZMinMax(&zmin, &zmax, vert+(i-1)*4);
ZMinMax(&zmin, &zmax, vert+i*4);
FOUND();
}
}
break;
case GL_TRIANGLE_FAN:
if (i>1) {
if (select_triangle_in_viewscreen(vert2, vert2+(i-1)*4, vert2+i*4)) {
ZMinMax(&zmin, &zmax, vert);
ZMinMax(&zmin, &zmax, vert+(i-1)*4);
ZMinMax(&zmin, &zmax, vert+i*4);
FOUND();
}
}
break;
default:
return; // Should never go there!
}
}
free(vert);
if(found) {
if (zmin<glstate->selectbuf.zmin) glstate->selectbuf.zmin=zmin;
if (zmax>glstate->selectbuf.zmax) glstate->selectbuf.zmax=zmax;
}
#undef FOUND
}
void select_glDrawElements(const pointer_state_t* vtx, GLenum mode, GLuint count, GLenum type, GLvoid * indices) {
if (count == 0) return;
if (vtx->pointer == NULL) return;
GLushort *ind = (GLushort*)indices;
GLsizei min, max;
getminmax_indices(indices, &max, &min, count);
max++;
GLfloat *vert = copy_gl_array(vtx->pointer, vtx->type,
vtx->size, vtx->stride,
GL_FLOAT, 3, 0, max);
GLfloat tmp[3];
init_select();
GLfloat zmin=1.0f, zmax=0.0f;
for (int i=min; i<max; i++) {
select_transform(vert+i*3);
if (vert[i*3+2]<zmin) zmin=vert[i*3+2];
if (vert[i*3+2]>zmax) zmax=vert[i*3+2];
}
if (zmin<0.0f) zmin = 0.0f;
if (zmax>1.0f) zmax = 1.0f;
#define FOUND() { \
if (zmin<state.selectbuf.zmin) state.selectbuf.zmin=zmin; \
if (zmax>state.selectbuf.zmax) state.selectbuf.zmax=zmax; \
state.selectbuf.hit = 1; \
free(vert); \
return; \
}
for (int i=0; i<count; i++) {
switch (mode) {
case GL_POINTS:
if (select_point_in_viewscreen(vert+ind[i]*3))
FOUND();
break;
case GL_LINES:
if (i%2==1) {
if (select_segment_in_viewscreen(vert+ind[(i-1)]*3, vert+ind[i]*3))
FOUND();
}
break;
case GL_LINE_STRIP:
case GL_LINE_LOOP: //FIXME: the last "loop" segment is missing here
if (i>0) {
if (select_segment_in_viewscreen(vert+ind[(i-1)]*3, vert+ind[i]*3))
FOUND();
}
break;
case GL_TRIANGLES:
if (i%3==2) {
if (select_triangle_in_viewscreen(vert+ind[(i-2)]*3, vert+ind[(i-1)]*3, vert+ind[i]*3))
FOUND();
}
break;
case GL_TRIANGLE_STRIP:
if (i>1) {
if (select_triangle_in_viewscreen(vert+ind[(i-2)]*3, vert+ind[(i-1)]*3, vert+ind[i]*3))
FOUND();
}
break;
case GL_TRIANGLE_FAN:
if (i>1) {
if (select_triangle_in_viewscreen(vert+ind[0]*3, vert+ind[(i-1)]*3, vert+ind[i]*3))
FOUND();
}
break;
default:
return; // Should never go there!
}
}
free(vert);
#undef FOUND
}
void select_glDrawArrays(const pointer_state_t* vtx, GLenum mode, GLuint first, GLuint count) {
if (count == 0) return;
if (vtx->pointer == NULL) return;
if (state.selectbuf.buffer == NULL) return;
GLfloat *vert = copy_gl_array(vtx->pointer, vtx->type,
vtx->size, vtx->stride,
GL_FLOAT, 3, 0, count+first);
GLfloat tmp[3];
GLfloat zmin=1.0f, zmax=0.0f;
init_select();
#define FOUND() { \
if (zmin<state.selectbuf.zmin) state.selectbuf.zmin=zmin; \
if (zmax>state.selectbuf.zmax) state.selectbuf.zmax=zmax; \
state.selectbuf.hit = 1; \
free(vert); \
return; \
}
// transform the points
for (int i=first; i<count+first; i++) {
select_transform(vert+i*3);
if (vert[i*3+2]<zmin) zmin=vert[i*3+2];
if (vert[i*3+2]>zmax) zmax=vert[i*3+2];
}
// intersect with screen now
GLfloat *vert2 = vert + first*3;
for (int i=0; i<count; i++) {
switch (mode) {
case GL_POINTS:
if (select_point_in_viewscreen(vert2+i*3))
FOUND();
break;
case GL_LINES:
if (i%2==1) {
if (select_segment_in_viewscreen(vert2+(i-1)*3, vert2+i*3))
FOUND();
}
break;
case GL_LINE_STRIP:
case GL_LINE_LOOP: //FIXME: the last "loop" segment is missing here
if (i>0) {
if (select_segment_in_viewscreen(vert2+(i-1)*3, vert2+i*3))
FOUND();
}
break;
case GL_TRIANGLES:
if (i%3==2) {
if (select_triangle_in_viewscreen(vert2+(i-2)*3, vert2+(i-1)*3, vert2+i*3))
FOUND();
}
break;
case GL_TRIANGLE_STRIP:
if (i>1) {
if (select_triangle_in_viewscreen(vert2+(i-2)*3, vert2+(i-1)*3, vert2+i*3))
FOUND();
}
break;
case GL_TRIANGLE_FAN:
if (i>1) {
if (select_triangle_in_viewscreen(vert2, vert2+(i-1)*3, vert2+i*3))
FOUND();
}
break;
default:
return; // Should never go there!
}
}
free(vert);
#undef FOUND
}
