static void key(GLFWwindow* window, int key, int scancode, int action, int mods)
{
TESS_NOTUSED(scancode);
TESS_NOTUSED(mods);
if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)
glfwSetWindowShouldClose(window, GL_TRUE);
if (key == GLFW_KEY_SPACE && action == GLFW_PRESS)
run = !run;
}
void* stdAlloc(void* userData, unsigned int size)
{
int* allocated = ( int*)userData;
TESS_NOTUSED(userData);
*allocated += (int)size;
return malloc(size);
}
static void GetIntersectData( TESStesselator *tess, TESSvertex *isect,
TESSvertex *orgUp, TESSvertex *dstUp,
TESSvertex *orgLo, TESSvertex *dstLo )
/*
* We've computed a new intersection point, now we need a "data" pointer
* from the user so that we can refer to this new vertex in the
* rendering callbacks.
*/
{
TESSreal weights[4];
TESS_NOTUSED( tess );
isect->coords[0] = isect->coords[1] = isect->coords[2] = 0;
isect->idx = TESS_UNDEF;
VertexWeights( isect, orgUp, dstUp, &weights[0] );
VertexWeights( isect, orgLo, dstLo, &weights[2] );
}
void heapFree( void* userData, void* ptr )
{
TESS_NOTUSED( userData );
free( ptr );
}
void* heapRealloc( void *userData, void* ptr, unsigned int size )
{
TESS_NOTUSED( userData );
return realloc( ptr, size );
}
void* heapAlloc( void* userData, unsigned int size )
{
TESS_NOTUSED( userData );
return malloc( size );
}
void poolFree( void* userData, void* ptr )
{
// empty
TESS_NOTUSED(userData);
TESS_NOTUSED(ptr);
}
int main(int argc, char *argv[])
{
GLFWwindow* window;
const GLFWvidmode* mode;
int width,height,i,j;
struct SVGPath* bg;
struct SVGPath* fg;
struct SVGPath* it;
float bounds[4],view[4],cx,cy,w,offx,offy;
float t = 0.0f, pt = 0.0f;
TESSalloc ma;
TESStesselator* tess = 0;
const int nvp = 6;
unsigned char* vflags = 0;
int nvflags = 0;
#ifdef USE_POOL
struct MemPool pool;
unsigned char mem[1024*1024];
#else
int allocated = 0;
#endif
TESS_NOTUSED(argc);
TESS_NOTUSED(argv);
if (!glfwInit()) {
printf("Failed to init GLFW.");
return -1;
}
printf("loading...\n");
// Load assets
bg = svgParseFromFile("../Bin/bg.svg");
if (!bg) return -1;
fg = svgParseFromFile("../Bin/fg.svg");
if (!fg) return -1;
printf("go...\n");
// Flip y
for (it = bg; it != NULL; it = it->next)
for (i = 0; i < it->npts; ++i)
it->pts[i*2+1] = -it->pts[i*2+1];
for (it = fg; it != NULL; it = it->next)
for (i = 0; i < it->npts; ++i)
it->pts[i*2+1] = -it->pts[i*2+1];
// Find FG bounds and center.
bounds[0] = bounds[2] = fg->pts[0];
bounds[1] = bounds[3] = fg->pts[1];
for (it = fg; it != NULL; it = it->next)
{
for (i = 0; i < it->npts; ++i)
{
const float x = it->pts[i*2];
const float y = it->pts[i*2+1];
if (x < bounds[0]) bounds[0] = x;
if (y < bounds[1]) bounds[1] = y;
if (x > bounds[2]) bounds[2] = x;
if (y > bounds[3]) bounds[3] = y;
}
}
cx = (bounds[0]+bounds[2])/2;
cy = (bounds[1]+bounds[3])/2;
for (it = fg; it != NULL; it = it->next)
{
for (i = 0; i < it->npts; ++i)
{
it->pts[i*2] -= cx;
it->pts[i*2+1] -= cy;
}
}
// Find BG bounds.
bounds[0] = bounds[2] = bg->pts[0];
bounds[1] = bounds[3] = bg->pts[1];
for (it = bg; it != NULL; it = it->next)
{
for (i = 0; i < it->npts; ++i)
{
const float x = it->pts[i*2];
const float y = it->pts[i*2+1];
if (x < bounds[0]) bounds[0] = x;
if (y < bounds[1]) bounds[1] = y;
if (x > bounds[2]) bounds[2] = x;
if (y > bounds[3]) bounds[3] = y;
}
}
#ifdef USE_POOL
pool.size = 0;
pool.cap = sizeof(mem);
pool.buf = mem;
memset(&ma, 0, sizeof(ma));
ma.memalloc = poolAlloc;
ma.memfree = poolFree;
ma.userData = (void*)&pool;
ma.extraVertices = 256; // realloc not provided, allow 256 extra vertices.
#else
memset(&ma, 0, sizeof(ma));
ma.memalloc = stdAlloc;
ma.memfree = stdFree;
ma.userData = (void*)&allocated;
ma.extraVertices = 256; // realloc not provided, allow 256 extra vertices.
tess = tessNewTess(&ma);
if (!tess)
return -1;
// Offset the foreground shape to center of the bg.
offx = (bounds[2]+bounds[0])/2;
offy = (bounds[3]+bounds[1])/2;
for (it = fg; it != NULL; it = it->next)
{
for (i = 0; i < it->npts; ++i)
{
it->pts[i*2] += offx;
it->pts[i*2+1] += offy;
}
}
// Add contours.
for (it = bg; it != NULL; it = it->next)
tessAddContour(tess, 2, it->pts, sizeof(float)*2, it->npts);
for (it = fg; it != NULL; it = it->next)
tessAddContour(tess, 2, it->pts, sizeof(float)*2, it->npts);
if (!tessTesselate(tess, TESS_WINDING_POSITIVE, TESS_POLYGONS, nvp, 2, 0))
return -1;
printf("Memory used: %.1f kB\n", allocated/1024.0f);
#endif
mode = glfwGetVideoMode(glfwGetPrimaryMonitor());
width = mode->width - 40;
height = mode->height - 80;
window = glfwCreateWindow(width, height, "Libtess2 Demo", NULL, NULL);
if (!window) {
glfwTerminate();
return -1;
}
glfwSetKeyCallback(window, key);
glfwMakeContextCurrent(window);
// Adjust bounds so that we get nice view of the bg.
cx = (bounds[0]+bounds[2])/2;
cy = (bounds[3]+bounds[1])/2;
w = (bounds[2]-bounds[0])/2;
view[0] = cx - w*1.2f;
view[2] = cx + w*1.2f;
view[1] = cy - w*1.2f*(float)height/(float)width;
view[3] = cy + w*1.2f*(float)height/(float)width;
glfwSetTime(0);
while (!glfwWindowShouldClose(window))
{
float ct = (float)glfwGetTime();
if (run) t += ct - pt;
pt = ct;
// Update and render
glViewport(0, 0, width, height);
glClearColor(0.3f, 0.3f, 0.32f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glDisable(GL_TEXTURE_2D);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(view[0],view[2],view[1],view[3],-1,1);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glDisable(GL_DEPTH_TEST);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);
#ifdef USE_POOL
pool.size = 0; // reset pool
tess = tessNewTess(&ma);
if (tess)
{
offx = (view[2]+view[0])/2 + sinf(t) * (view[2]-view[0])/2;
offy = (view[3]+view[1])/2 + cosf(t*3.13f) * (view[3]-view[1])/6;
for (it = fg; it != NULL; it = it->next)
{
for (i = 0; i < it->npts; ++i)
{
it->pts[i*2] += offx;
it->pts[i*2+1] += offy;
}
}
for (it = bg; it != NULL; it = it->next)
tessAddContour(tess, 2, it->pts, sizeof(float)*2, it->npts);
for (it = fg; it != NULL; it = it->next)
tessAddContour(tess, 2, it->pts, sizeof(float)*2, it->npts);
for (it = fg; it != NULL; it = it->next)
{
for (i = 0; i < it->npts; ++i)
{
it->pts[i*2] -= offx;
it->pts[i*2+1] -= offy;
}
}
// First combine contours and then triangulate, this removes unnecessary inner vertices.
if (tessTesselate(tess, TESS_WINDING_POSITIVE, TESS_BOUNDARY_CONTOURS, 0, 0, 0))
{
const float* verts = tessGetVertices(tess);
const int* vinds = tessGetVertexIndices(tess);
const int nverts = tessGetVertexCount(tess);
const int* elems = tessGetElements(tess);
const int nelems = tessGetElementCount(tess);
if (nverts > nvflags)
{
if (vflags)
free(vflags);
nvflags = nverts;
vflags = (unsigned char*)malloc(sizeof(unsigned char)*nvflags);
}
if (vflags)
{
// Vertex indices describe the order the indices were added and can be used
// to map the tesselator output to input. Vertices marked as TESS_UNDEF
// are the ones that were created at the intersection of segments.
// That is, if vflags is set it means that the vertex comes from intersegment.
for (i = 0; i < nverts; ++i)
vflags[i] = vinds[i] == TESS_UNDEF ? 1 : 0;
}
for (i = 0; i < nelems; ++i)
{
int b = elems[i*2];
int n = elems[i*2+1];
tessAddContour(tess, 2, &verts[b*2], sizeof(float)*2, n);
}
if (!tessTesselate(tess, TESS_WINDING_POSITIVE, TESS_POLYGONS, nvp, 2, 0))
tess = 0;
}
else
tess = 0;
}
#endif
// Draw tesselated pieces.
if (tess)
{
const float* verts = tessGetVertices(tess);
const int* vinds = tessGetVertexIndices(tess);
const int* elems = tessGetElements(tess);
const int nverts = tessGetVertexCount(tess);
const int nelems = tessGetElementCount(tess);
// Draw polygons.
glColor4ub(255,255,255,128);
for (i = 0; i < nelems; ++i)
{
const int* p = &elems[i*nvp];
glBegin(GL_TRIANGLE_FAN);
for (j = 0; j < nvp && p[j] != TESS_UNDEF; ++j)
glVertex2f(verts[p[j]*2], verts[p[j]*2+1]);
glEnd();
}
glColor4ub(0,0,0,16);
for (i = 0; i < nelems; ++i)
{
const int* p = &elems[i*nvp];
glBegin(GL_LINE_LOOP);
for (j = 0; j < nvp && p[j] != TESS_UNDEF; ++j)
glVertex2f(verts[p[j]*2], verts[p[j]*2+1]);
glEnd();
}
glColor4ub(0,0,0,128);
glPointSize(3.0f);
glBegin(GL_POINTS);
for (i = 0; i < nverts; ++i)
{
if (vflags && vflags[vinds[i]])
glColor4ub(255,0,0,192);
else
glColor4ub(0,0,0,128);
glVertex2f(verts[i*2], verts[i*2+1]);
}
glEnd();
glPointSize(1.0f);
}
glEnable(GL_DEPTH_TEST);
glfwSwapBuffers(window);
glfwPollEvents();
}
if (tess) tessDeleteTess(tess);
if (vflags)
free(vflags);
svgDelete(bg);
svgDelete(fg);
glfwTerminate();
return 0;
}
