[ui, layout] solving layout constraints

This commit is contained in:
Martin Fouilleul 2023-03-09 13:13:13 +01:00
parent 56874c99d6
commit d2f4f5083b
1 changed files with 56 additions and 92 deletions

138
src/ui.c
View File

@ -979,50 +979,60 @@ void ui_styling_prepass(ui_context* ui, ui_box* box, list_info* before, list_inf
} }
} }
bool ui_layout_downward_dependency(ui_box* child, int axis)
{
return( !ui_box_hidden(child)
&& !child->style.floating.c[axis]
&& child->style.size.c[axis].kind != UI_SIZE_PARENT
&& child->style.size.c[axis].kind != UI_SIZE_PARENT_MINUS_PIXELS);
}
void ui_layout_downward_dependent_size(ui_context* ui, ui_box* box, int axis) void ui_layout_downward_dependent_size(ui_context* ui, ui_box* box, int axis)
{ {
f32 sum = 0; //NOTE: layout children and compute spacing
f32 count = 0; f32 count = 0;
if(box->style.layout.axis == axis)
{
int count = 0;
for_list(&box->children, child, ui_box, listElt) for_list(&box->children, child, ui_box, listElt)
{ {
if(!ui_box_hidden(child)) if(!ui_box_hidden(child))
{ {
ui_layout_downward_dependent_size(ui, child, axis); ui_layout_downward_dependent_size(ui, child, axis);
if(!child->style.floating.c[axis])
if( box->style.layout.axis == axis
&& !child->style.floating.c[axis])
{ {
//TODO: maybe log an error if child is dependant on parent
sum += child->rect.c[2+axis];
count++; count++;
} }
} }
} }
box->spacing[axis] = maximum(0, count-1)*box->style.layout.spacing; box->spacing[axis] = maximum(0, count-1)*box->style.layout.spacing;
ui_size* size = &box->style.size.c[axis];
if(size->kind == UI_SIZE_CHILDREN)
{
//NOTE: if box is dependent on children, compute children's size. If we're in the layout
// axis this is the sum of each child size, otherwise it is the maximum child size
f32 sum = 0;
if(box->style.layout.axis == axis)
{
for_list(&box->children, child, ui_box, listElt)
{
if(ui_layout_downward_dependency(child, axis))
{
sum += child->rect.c[2+axis];
}
}
} }
else else
{ {
for_list(&box->children, child, ui_box, listElt) for_list(&box->children, child, ui_box, listElt)
{ {
if(!ui_box_hidden(child)) if(ui_layout_downward_dependency(child, axis))
{
ui_layout_downward_dependent_size(ui, child, axis);
if(!child->style.floating.c[axis])
{ {
sum = maximum(sum, child->rect.c[2+axis]); sum = maximum(sum, child->rect.c[2+axis]);
} }
} }
} }
box->spacing[axis] = 0;
}
box->childrenSum[axis] = sum;
ui_size* size = &box->style.size.c[axis];
if(size->kind == UI_SIZE_CHILDREN)
{
f32 margin = box->style.layout.margin.c[axis]; f32 margin = box->style.layout.margin.c[axis];
box->rect.c[2+axis] = sum + box->spacing[axis] + 2*margin; box->rect.c[2+axis] = sum + box->spacing[axis] + 2*margin;
} }
@ -1030,81 +1040,49 @@ void ui_layout_downward_dependent_size(ui_context* ui, ui_box* box, int axis)
void ui_layout_upward_dependent_size(ui_context* ui, ui_box* box, int axis) void ui_layout_upward_dependent_size(ui_context* ui, ui_box* box, int axis)
{ {
if(ui_box_hidden(box)) //NOTE: compute size of children that depend on box's size, and also compute
{ // total children sum and total slack available in layout axis
return;
}
ui_size* size = &box->style.size.c[axis];
if(size->kind == UI_SIZE_PARENT)
{
ui_box* parent = box->parent;
if(parent)
{
f32 margin = parent->style.layout.margin.c[axis];
box->rect.c[2+axis] = maximum(0, parent->rect.c[2+axis] - parent->spacing[axis] - 2*margin) * size->value;
}
}
else if(size->kind == UI_SIZE_PARENT_MINUS_PIXELS)
{
ui_box* parent = box->parent;
if(parent)
{
f32 margin = parent->style.layout.margin.c[axis];
box->rect.c[2+axis] = maximum(0, parent->rect.c[2+axis] - parent->spacing[axis] - 2*margin - size->value);
}
}
for_list(&box->children, child, ui_box, listElt)
{
ui_layout_upward_dependent_size(ui, child, axis);
}
}
void ui_layout_solve_conflicts(ui_context* ui, ui_box* box, int axis)
{/*
f32 totalContents = box->childrenSum[axis]
+ box->spacing[axis]
+ 2*box->style.layout.margin.c[axis];
*/
f32 sum = 0;
if(box->style.layout.axis == axis)
{
//NOTE: if we're solving in the layout axis, first recompute the total size
// and total slack of children.
//NOTE: we also recompute children that depend on the parent. Maybe we could combine with upward dependent stuff...
f32 margin = box->style.layout.margin.c[axis]; f32 margin = box->style.layout.margin.c[axis];
f32 parentAvailableSize = maximum(0, box->rect.c[2+axis] - box->spacing[axis] - 2*margin); f32 availableSize = maximum(0, box->rect.c[2+axis] - box->spacing[axis] - 2*margin);
f32 slack = 0;
for_list(&box->children, child, ui_box, listElt) for_list(&box->children, child, ui_box, listElt)
{ {
ui_size* size = &child->style.size.c[axis]; ui_size* size = &child->style.size.c[axis];
if(size->kind == UI_SIZE_PARENT) if(size->kind == UI_SIZE_PARENT)
{ {
child->rect.c[2+axis] = parentAvailableSize * size->value; child->rect.c[2+axis] = availableSize * size->value;
} }
else if(size->kind == UI_SIZE_PARENT_MINUS_PIXELS) else if(size->kind == UI_SIZE_PARENT_MINUS_PIXELS)
{ {
child->rect.c[2+axis] = maximum(0, parentAvailableSize - size->value); child->rect.c[2+axis] = maximum(0, availableSize - size->value);
}
} }
if(!ui_box_hidden(child) && !child->style.floating.c[axis]) //NOTE: solve downard conflicts
f32 sum = 0;
if(box->style.layout.axis == axis)
{
//NOTE: if we're solving in the layout axis, first compute total sum of children and
// total slack available
f32 slack = 0;
for_list(&box->children, child, ui_box, listElt)
{
if( !ui_box_hidden(child)
&& !child->style.floating.c[axis])
{ {
sum += child->rect.c[2+axis]; sum += child->rect.c[2+axis];
slack += child->rect.c[2+axis] * child->style.size.c[axis].relax; slack += child->rect.c[2+axis] * child->style.size.c[axis].relax;
} }
} }
//NOTE: then remove excess proportionally to each box slack, and recompute children sum.
f32 totalContents = sum + box->spacing[axis] + 2*box->style.layout.margin.c[axis]; f32 totalContents = sum + box->spacing[axis] + 2*box->style.layout.margin.c[axis];
f32 excess = ClampLowBound(totalContents - box->rect.c[2+axis], 0); f32 excess = ClampLowBound(totalContents - box->rect.c[2+axis], 0);
f32 alpha = Clamp(excess / slack, 0, 1); f32 alpha = Clamp(excess / slack, 0, 1);
//NOTE: then remove excess proportionally to each box slack, and recompute children sum.
sum = 0; sum = 0;
for_list(&box->children, child, ui_box, listElt) for_list(&box->children, child, ui_box, listElt)
{ {
@ -1118,21 +1096,8 @@ void ui_layout_solve_conflicts(ui_context* ui, ui_box* box, int axis)
//NOTE: if we're solving on the secondary axis, we remove excess to each box individually //NOTE: if we're solving on the secondary axis, we remove excess to each box individually
// according to its own slack. Children sum is the maximum child size. // according to its own slack. Children sum is the maximum child size.
f32 margin = box->style.layout.margin.c[axis];
f32 parentAvailableSize = maximum(0, box->rect.c[2+axis] - box->spacing[axis] - 2*margin);
for_list(&box->children, child, ui_box, listElt) for_list(&box->children, child, ui_box, listElt)
{ {
ui_size* size = &child->style.size.c[axis];
if(size->kind == UI_SIZE_PARENT)
{
child->rect.c[2+axis] = parentAvailableSize * size->value;
}
else if(size->kind == UI_SIZE_PARENT_MINUS_PIXELS)
{
child->rect.c[2+axis] = maximum(0, parentAvailableSize - size->value);
}
if(!ui_box_hidden(child) && !child->style.floating.c[axis]) if(!ui_box_hidden(child) && !child->style.floating.c[axis])
{ {
f32 totalContents = child->rect.c[2+axis] + 2*box->style.layout.margin.c[axis]; f32 totalContents = child->rect.c[2+axis] + 2*box->style.layout.margin.c[axis];
@ -1151,7 +1116,7 @@ void ui_layout_solve_conflicts(ui_context* ui, ui_box* box, int axis)
//NOTE: recurse in children //NOTE: recurse in children
for_list(&box->children, child, ui_box, listElt) for_list(&box->children, child, ui_box, listElt)
{ {
ui_layout_solve_conflicts(ui, child, axis); ui_layout_upward_dependent_size(ui, child, axis);
} }
} }
@ -1270,7 +1235,6 @@ void ui_solve_layout(ui_context* ui)
{ {
ui_layout_downward_dependent_size(ui, ui->root, axis); ui_layout_downward_dependent_size(ui, ui->root, axis);
ui_layout_upward_dependent_size(ui, ui->root, axis); ui_layout_upward_dependent_size(ui, ui->root, axis);
ui_layout_solve_conflicts(ui, ui->root, axis);
} }
ui_layout_compute_rect(ui, ui->root, (vec2){0, 0}); ui_layout_compute_rect(ui, ui->root, (vec2){0, 0});