solvespace/src/glhelper.cpp

728 lines
20 KiB
C++

//-----------------------------------------------------------------------------
// Helper functions that ultimately draw stuff with gl.
//
// Copyright 2008-2013 Jonathan Westhues.
//-----------------------------------------------------------------------------
#include <zlib.h>
#include "solvespace.h"
namespace SolveSpace {
// A vector font.
#include "generated/vectorfont.table.h"
// A bitmap font.
#include "generated/bitmapfont.table.h"
static bool ColorLocked;
static bool DepthOffsetLocked;
static const VectorGlyph &GetVectorGlyph(char32_t chr) {
int first = 0;
int last = sizeof(VectorFont) / sizeof(VectorGlyph);
while(first <= last) {
int mid = (first + last) / 2;
char32_t midChr = VectorFont[mid].character;
if(midChr > chr) {
last = mid - 1; // and first stays the same
continue;
}
if(midChr < chr) {
first = mid + 1; // and last stays the same
continue;
}
return VectorFont[mid];
}
return GetVectorGlyph(0xfffd); // replacement character
}
#define FONT_SCALE(h) ((h)/87.0)
double ssglStrWidth(const std::string &str, double h)
{
int width = 0;
for(char32_t chr : ReadUTF8(str)) {
const VectorGlyph &glyph = GetVectorGlyph(chr);
if(glyph.baseCharacter != 0) {
const VectorGlyph &baseGlyph = GetVectorGlyph(glyph.baseCharacter);
width += max(glyph.width, baseGlyph.width);
} else {
width += glyph.width;
}
}
return width * FONT_SCALE(h) / SS.GW.scale;
}
double ssglStrHeight(double h)
{
// The characters have height ~90, as they appear in the table.
return 90.0 * FONT_SCALE(h) / SS.GW.scale;
}
void ssglWriteTextRefCenter(const std::string &str, double h, Vector t, Vector u, Vector v,
ssglLineFn *fn, void *fndata)
{
u = u.WithMagnitude(1);
v = v.WithMagnitude(1);
double scale = FONT_SCALE(h)/SS.GW.scale;
double fh = ssglStrHeight(h);
double fw = ssglStrWidth(str, h);
t = t.Plus(u.ScaledBy(-fw/2));
t = t.Plus(v.ScaledBy(-fh/2));
// Undo the (+5, +5) offset that ssglWriteText applies.
t = t.Plus(u.ScaledBy(-5*scale));
t = t.Plus(v.ScaledBy(-5*scale));
ssglWriteText(str, h, t, u, v, fn, fndata);
}
void ssglLineWidth(GLfloat width) {
// Intel GPUs with Mesa on *nix render thin lines poorly.
static bool workaroundChecked, workaroundEnabled;
if(!workaroundChecked) {
// ssglLineWidth can be called before GL is initialized
if(glGetString(GL_VENDOR)) {
workaroundChecked = true;
if(!strcmp((char*)glGetString(GL_VENDOR), "Intel Open Source Technology Center"))
workaroundEnabled = true;
}
}
if(workaroundEnabled && width < 1.6f)
width = 1.6f;
glLineWidth(width);
}
static void LineDrawCallback(void *fndata, Vector a, Vector b)
{
ssglLineWidth(1);
glBegin(GL_LINES);
ssglVertex3v(a);
ssglVertex3v(b);
glEnd();
}
int ssglDrawCharacter(const VectorGlyph &glyph, Vector t, Vector o, Vector u, Vector v,
double scale, ssglLineFn *fn, void *fndata) {
int width = glyph.width;
if(glyph.baseCharacter != 0) {
const VectorGlyph &baseGlyph = GetVectorGlyph(glyph.baseCharacter);
int baseWidth = ssglDrawCharacter(baseGlyph, t, o, u, v, scale, fn, fndata);
width = max(glyph.width, baseWidth);
}
const int8_t *data = glyph.data;
bool pen_up = true;
Vector prevp;
while(true) {
int8_t x = *data++;
int8_t y = *data++;
if(x == PEN_UP && y == PEN_UP) {
if(pen_up) break;
pen_up = true;
} else {
Vector p = t;
p = p.Plus(u.ScaledBy((o.x + x) * scale));
p = p.Plus(v.ScaledBy((o.y + y) * scale));
if(!pen_up) fn(fndata, prevp, p);
prevp = p;
pen_up = false;
}
}
return width;
}
void ssglWriteText(const std::string &str, double h, Vector t, Vector u, Vector v,
ssglLineFn *fn, void *fndata)
{
if(!fn) fn = LineDrawCallback;
u = u.WithMagnitude(1);
v = v.WithMagnitude(1);
double scale = FONT_SCALE(h) / SS.GW.scale;
Vector o = { 5.0, 5.0 };
for(char32_t chr : ReadUTF8(str)) {
const VectorGlyph &glyph = GetVectorGlyph(chr);
o.x += ssglDrawCharacter(glyph, t, o, u, v, scale, fn, fndata);
}
}
void ssglVertex3v(Vector u)
{
glVertex3f((GLfloat)u.x, (GLfloat)u.y, (GLfloat)u.z);
}
void ssglAxisAlignedQuad(double l, double r, double t, double b, bool lone)
{
if(lone) glBegin(GL_QUADS);
glVertex2d(l, t);
glVertex2d(l, b);
glVertex2d(r, b);
glVertex2d(r, t);
if(lone) glEnd();
}
void ssglAxisAlignedLineLoop(double l, double r, double t, double b)
{
glBegin(GL_LINE_LOOP);
glVertex2d(l, t);
glVertex2d(l, b);
glVertex2d(r, b);
glVertex2d(r, t);
glEnd();
}
static void FatLineEndcap(Vector p, Vector u, Vector v)
{
// A table of cos and sin of (pi*i/10 + pi/2), as i goes from 0 to 10
static const double Circle[11][2] = {
{ 0.0000, 1.0000 },
{ -0.3090, 0.9511 },
{ -0.5878, 0.8090 },
{ -0.8090, 0.5878 },
{ -0.9511, 0.3090 },
{ -1.0000, 0.0000 },
{ -0.9511, -0.3090 },
{ -0.8090, -0.5878 },
{ -0.5878, -0.8090 },
{ -0.3090, -0.9511 },
{ 0.0000, -1.0000 },
};
glBegin(GL_TRIANGLE_FAN);
for(int i = 0; i <= 10; i++) {
double c = Circle[i][0], s = Circle[i][1];
ssglVertex3v(p.Plus(u.ScaledBy(c)).Plus(v.ScaledBy(s)));
}
glEnd();
}
void ssglFatLine(Vector a, Vector b, double width)
{
// The half-width of the line we're drawing.
double hw = width / 2;
Vector ab = b.Minus(a);
Vector gn = (SS.GW.projRight).Cross(SS.GW.projUp);
Vector abn = (ab.Cross(gn)).WithMagnitude(1);
abn = abn.Minus(gn.ScaledBy(gn.Dot(abn)));
// So now abn is normal to the projection of ab into the screen, so the
// line will always have constant thickness as the view is rotated.
abn = abn.WithMagnitude(hw);
ab = gn.Cross(abn);
ab = ab. WithMagnitude(hw);
// The body of a line is a quad
glBegin(GL_QUADS);
ssglVertex3v(a.Minus(abn));
ssglVertex3v(b.Minus(abn));
ssglVertex3v(b.Plus (abn));
ssglVertex3v(a.Plus (abn));
glEnd();
// And the line has two semi-circular end caps.
FatLineEndcap(a, ab, abn);
FatLineEndcap(b, ab.ScaledBy(-1), abn);
}
void ssglLockColorTo(RgbaColor rgb)
{
ColorLocked = false;
glColor3d(rgb.redF(), rgb.greenF(), rgb.blueF());
ColorLocked = true;
}
void ssglUnlockColor(void)
{
ColorLocked = false;
}
void ssglColorRGB(RgbaColor rgb)
{
// Is there a bug in some graphics drivers where this is not equivalent
// to glColor3d? There seems to be...
ssglColorRGBa(rgb, 1.0);
}
void ssglColorRGBa(RgbaColor rgb, double a)
{
if(!ColorLocked) glColor4d(rgb.redF(), rgb.greenF(), rgb.blueF(), a);
}
static void Stipple(bool forSel)
{
static bool Init;
const int BYTES = (32*32)/8;
static GLubyte HoverMask[BYTES];
static GLubyte SelMask[BYTES];
if(!Init) {
int x, y;
for(x = 0; x < 32; x++) {
for(y = 0; y < 32; y++) {
int i = y*4 + x/8, b = x % 8;
int ym = y % 4, xm = x % 4;
for(int k = 0; k < 2; k++) {
if(xm >= 1 && xm <= 2 && ym >= 1 && ym <= 2) {
(k == 0 ? SelMask : HoverMask)[i] |= (0x80 >> b);
}
ym = (ym + 2) % 4; xm = (xm + 2) % 4;
}
}
}
Init = true;
}
glEnable(GL_POLYGON_STIPPLE);
if(forSel) {
glPolygonStipple(SelMask);
} else {
glPolygonStipple(HoverMask);
}
}
static void StippleTriangle(STriangle *tr, bool s, RgbaColor rgb)
{
glEnd();
glDisable(GL_LIGHTING);
ssglColorRGB(rgb);
Stipple(s);
glBegin(GL_TRIANGLES);
ssglVertex3v(tr->a);
ssglVertex3v(tr->b);
ssglVertex3v(tr->c);
glEnd();
glEnable(GL_LIGHTING);
glDisable(GL_POLYGON_STIPPLE);
glBegin(GL_TRIANGLES);
}
void ssglFillMesh(bool useSpecColor, RgbaColor specColor,
SMesh *m, uint32_t h, uint32_t s1, uint32_t s2)
{
RgbaColor rgbHovered = Style::Color(Style::HOVERED),
rgbSelected = Style::Color(Style::SELECTED);
glEnable(GL_NORMALIZE);
bool hasMaterial = false;
RgbaColor prevColor;
glBegin(GL_TRIANGLES);
for(int i = 0; i < m->l.n; i++) {
STriangle *tr = &(m->l.elem[i]);
RgbaColor color;
if(useSpecColor) {
color = specColor;
} else {
color = tr->meta.color;
}
if(!hasMaterial || !color.Equals(prevColor)) {
GLfloat mpf[] = { color.redF(), color.greenF(), color.blueF(), color.alphaF() };
glEnd();
glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, mpf);
prevColor = color;
hasMaterial = true;
glBegin(GL_TRIANGLES);
}
if(tr->an.EqualsExactly(Vector::From(0, 0, 0))) {
// Compute the normal from the vertices
Vector n = tr->Normal();
glNormal3d(n.x, n.y, n.z);
ssglVertex3v(tr->a);
ssglVertex3v(tr->b);
ssglVertex3v(tr->c);
} else {
// Use the exact normals that are specified
glNormal3d((tr->an).x, (tr->an).y, (tr->an).z);
ssglVertex3v(tr->a);
glNormal3d((tr->bn).x, (tr->bn).y, (tr->bn).z);
ssglVertex3v(tr->b);
glNormal3d((tr->cn).x, (tr->cn).y, (tr->cn).z);
ssglVertex3v(tr->c);
}
if((s1 != 0 && tr->meta.face == s1) ||
(s2 != 0 && tr->meta.face == s2))
{
StippleTriangle(tr, true, rgbSelected);
}
if(h != 0 && tr->meta.face == h) {
StippleTriangle(tr, false, rgbHovered);
}
}
glEnd();
}
static void SSGL_CALLBACK Vertex(Vector *p)
{
ssglVertex3v(*p);
}
void ssglFillPolygon(SPolygon *p)
{
GLUtesselator *gt = gluNewTess();
gluTessCallback(gt, GLU_TESS_BEGIN, (ssglCallbackFptr *)glBegin);
gluTessCallback(gt, GLU_TESS_END, (ssglCallbackFptr *)glEnd);
gluTessCallback(gt, GLU_TESS_VERTEX, (ssglCallbackFptr *)Vertex);
ssglTesselatePolygon(gt, p);
gluDeleteTess(gt);
}
static void SSGL_CALLBACK Combine(double coords[3], void *vertexData[4],
float weight[4], void **outData)
{
Vector *n = (Vector *)AllocTemporary(sizeof(Vector));
n->x = coords[0];
n->y = coords[1];
n->z = coords[2];
*outData = n;
}
void ssglTesselatePolygon(GLUtesselator *gt, SPolygon *p)
{
int i, j;
gluTessCallback(gt, GLU_TESS_COMBINE, (ssglCallbackFptr *)Combine);
gluTessProperty(gt, GLU_TESS_WINDING_RULE, GLU_TESS_WINDING_ODD);
Vector normal = p->normal;
glNormal3d(normal.x, normal.y, normal.z);
gluTessNormal(gt, normal.x, normal.y, normal.z);
gluTessBeginPolygon(gt, NULL);
for(i = 0; i < p->l.n; i++) {
SContour *sc = &(p->l.elem[i]);
gluTessBeginContour(gt);
for(j = 0; j < (sc->l.n-1); j++) {
SPoint *sp = &(sc->l.elem[j]);
double ap[3];
ap[0] = sp->p.x;
ap[1] = sp->p.y;
ap[2] = sp->p.z;
gluTessVertex(gt, ap, &(sp->p));
}
gluTessEndContour(gt);
}
gluTessEndPolygon(gt);
}
void ssglDebugPolygon(SPolygon *p)
{
int i, j;
ssglLineWidth(2);
glPointSize(7);
glDisable(GL_DEPTH_TEST);
for(i = 0; i < p->l.n; i++) {
SContour *sc = &(p->l.elem[i]);
for(j = 0; j < (sc->l.n-1); j++) {
Vector a = (sc->l.elem[j]).p;
Vector b = (sc->l.elem[j+1]).p;
ssglLockColorTo(RGBi(0, 0, 255));
Vector d = (a.Minus(b)).WithMagnitude(-0);
glBegin(GL_LINES);
ssglVertex3v(a.Plus(d));
ssglVertex3v(b.Minus(d));
glEnd();
ssglLockColorTo(RGBi(255, 0, 0));
glBegin(GL_POINTS);
ssglVertex3v(a.Plus(d));
ssglVertex3v(b.Minus(d));
glEnd();
}
}
}
void ssglDrawEdges(SEdgeList *el, bool endpointsToo)
{
SEdge *se;
glBegin(GL_LINES);
for(se = el->l.First(); se; se = el->l.NextAfter(se)) {
ssglVertex3v(se->a);
ssglVertex3v(se->b);
}
glEnd();
if(endpointsToo) {
glPointSize(12);
glBegin(GL_POINTS);
for(se = el->l.First(); se; se = el->l.NextAfter(se)) {
ssglVertex3v(se->a);
ssglVertex3v(se->b);
}
glEnd();
}
}
void ssglDebugMesh(SMesh *m)
{
int i;
ssglLineWidth(1);
glPointSize(7);
ssglDepthRangeOffset(1);
ssglUnlockColor();
glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
ssglColorRGBa(RGBi(0, 255, 0), 1.0);
glBegin(GL_TRIANGLES);
for(i = 0; i < m->l.n; i++) {
STriangle *t = &(m->l.elem[i]);
if(t->tag) continue;
ssglVertex3v(t->a);
ssglVertex3v(t->b);
ssglVertex3v(t->c);
}
glEnd();
ssglDepthRangeOffset(0);
glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
}
void ssglMarkPolygonNormal(SPolygon *p)
{
Vector tail = Vector::From(0, 0, 0);
int i, j, cnt = 0;
// Choose some reasonable center point.
for(i = 0; i < p->l.n; i++) {
SContour *sc = &(p->l.elem[i]);
for(j = 0; j < (sc->l.n-1); j++) {
SPoint *sp = &(sc->l.elem[j]);
tail = tail.Plus(sp->p);
cnt++;
}
}
if(cnt == 0) return;
tail = tail.ScaledBy(1.0/cnt);
Vector gn = SS.GW.projRight.Cross(SS.GW.projUp);
Vector tip = tail.Plus((p->normal).WithMagnitude(40/SS.GW.scale));
Vector arrow = (p->normal).WithMagnitude(15/SS.GW.scale);
glColor3d(1, 1, 0);
glBegin(GL_LINES);
ssglVertex3v(tail);
ssglVertex3v(tip);
ssglVertex3v(tip);
ssglVertex3v(tip.Minus(arrow.RotatedAbout(gn, 0.6)));
ssglVertex3v(tip);
ssglVertex3v(tip.Minus(arrow.RotatedAbout(gn, -0.6)));
glEnd();
glEnable(GL_LIGHTING);
}
void ssglDepthRangeOffset(int units)
{
if(!DepthOffsetLocked) {
// The size of this step depends on the resolution of the Z buffer; for
// a 16-bit buffer, this should be fine.
double d = units/60000.0;
glDepthRange(0.1-d, 1-d);
}
}
void ssglDepthRangeLockToFront(bool yes)
{
if(yes) {
DepthOffsetLocked = true;
glDepthRange(0, 0);
} else {
DepthOffsetLocked = false;
ssglDepthRangeOffset(0);
}
}
const int BitmapFontChunkSize = 64 * 64;
static bool BitmapFontChunkInitialized[0x10000 / BitmapFontChunkSize];
static int BitmapFontCurrentChunk = -1;
static void CreateBitmapFontChunk(const uint8_t *source, size_t sourceLength,
int textureIndex)
{
// Place the font in our texture in a two-dimensional grid.
// The maximum texture size that is reasonably supported is 1024x1024.
const size_t fontTextureSize = BitmapFontChunkSize*16*16;
uint8_t *fontTexture = (uint8_t *)malloc(fontTextureSize),
*mappedTexture = (uint8_t *)malloc(fontTextureSize);
z_stream stream;
stream.zalloc = Z_NULL;
stream.zfree = Z_NULL;
stream.opaque = Z_NULL;
if(inflateInit(&stream) != Z_OK)
oops();
stream.next_in = (Bytef *)source;
stream.avail_in = sourceLength;
stream.next_out = fontTexture;
stream.avail_out = fontTextureSize;
if(inflate(&stream, Z_NO_FLUSH) != Z_STREAM_END)
oops();
if(stream.avail_out != 0)
oops();
inflateEnd(&stream);
for(int a = 0; a < BitmapFontChunkSize; a++) {
int row = a / 64, col = a % 64;
for(int i = 0; i < 16; i++) {
memcpy(mappedTexture + row*64*16*16 + col*16 + i*64*16,
fontTexture + a*16*16 + i*16,
16);
}
}
free(fontTexture);
glBindTexture(GL_TEXTURE_2D, textureIndex);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA,
16*64, 64*16,
0,
GL_ALPHA, GL_UNSIGNED_BYTE,
mappedTexture);
free(mappedTexture);
}
static void SwitchToBitmapFontChunkFor(char32_t chr)
{
int plane = chr / BitmapFontChunkSize,
textureIndex = TEXTURE_BITMAP_FONT + plane;
if(BitmapFontCurrentChunk != textureIndex) {
glEnd();
if(!BitmapFontChunkInitialized[plane]) {
CreateBitmapFontChunk(CompressedFontTexture[plane].data,
CompressedFontTexture[plane].length,
textureIndex);
BitmapFontChunkInitialized[plane] = true;
} else {
glBindTexture(GL_TEXTURE_2D, textureIndex);
}
BitmapFontCurrentChunk = textureIndex;
glBegin(GL_QUADS);
}
}
void ssglInitializeBitmapFont()
{
memset(BitmapFontChunkInitialized, 0, sizeof(BitmapFontChunkInitialized));
BitmapFontCurrentChunk = -1;
}
int ssglBitmapCharWidth(char32_t chr) {
if(!CodepointProperties[chr].exists)
oops();
return CodepointProperties[chr].isWide ? 2 : 1;
}
void ssglBitmapCharQuad(char32_t chr, double x, double y)
{
int w, h;
h = 16;
if(chr >= 0xe000 && chr <= 0xefff) {
// Special character, like a checkbox or a radio button
w = 16;
x -= 3;
} else if(CodepointProperties[chr].isWide) {
// Wide (usually CJK or reserved) character
w = 16;
} else {
// Normal character
w = 8;
}
if(chr != ' ' && chr != 0) {
int n = chr % BitmapFontChunkSize;
int row = n / 64, col = n % 64;
double s0 = col/64.0,
s1 = (col+1)/64.0,
t0 = row/64.0,
t1 = t0 + (w/16.0)/64;
SwitchToBitmapFontChunkFor(chr);
glTexCoord2d(s1, t0);
glVertex2d(x, y);
glTexCoord2d(s1, t1);
glVertex2d(x + w, y);
glTexCoord2d(s0, t1);
glVertex2d(x + w, y - h);
glTexCoord2d(s0, t0);
glVertex2d(x, y - h);
}
}
void ssglBitmapText(const std::string &str, Vector p)
{
glEnable(GL_TEXTURE_2D);
glBegin(GL_QUADS);
for(char32_t chr : ReadUTF8(str)) {
ssglBitmapCharQuad(chr, p.x, p.y);
p.x += 8 * ssglBitmapCharWidth(chr);
}
glEnd();
glDisable(GL_TEXTURE_2D);
}
void ssglDrawPixelsWithTexture(uint8_t *data, int w, int h)
{
#define MAX_DIM 32
static uint8_t Texture[MAX_DIM*MAX_DIM*3];
int i, j;
if(w > MAX_DIM || h > MAX_DIM) oops();
for(i = 0; i < w; i++) {
for(j = 0; j < h; j++) {
Texture[(j*MAX_DIM + i)*3 + 0] = data[(j*w + i)*3 + 0];
Texture[(j*MAX_DIM + i)*3 + 1] = data[(j*w + i)*3 + 1];
Texture[(j*MAX_DIM + i)*3 + 2] = data[(j*w + i)*3 + 2];
}
}
glBindTexture(GL_TEXTURE_2D, TEXTURE_DRAW_PIXELS);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, MAX_DIM, MAX_DIM, 0,
GL_RGB, GL_UNSIGNED_BYTE, Texture);
glEnable(GL_TEXTURE_2D);
glBegin(GL_QUADS);
glTexCoord2d(0, 0);
glVertex2d(0, h);
glTexCoord2d(((double)w)/MAX_DIM, 0);
glVertex2d(w, h);
glTexCoord2d(((double)w)/MAX_DIM, ((double)h)/MAX_DIM);
glVertex2d(w, 0);
glTexCoord2d(0, ((double)h)/MAX_DIM);
glVertex2d(0, 0);
glEnd();
glDisable(GL_TEXTURE_2D);
}
};