[Core] Improve & streamline grow / shrink handling (#296)

.github/workflows/cmake-multi-platform.yml

@@ -53,7 +53,7 @@ jobs:
         echo "build-output-dir=${{ github.workspace }}/build" >> "$GITHUB_OUTPUT"
 
     - name: Cache
-      uses: actions/cache@v4.0.2
+      uses: actions/cache@v4.2.0
       with:
         # A list of files, directories, and wildcard patterns to cache and restore
         path: "/home/runner/work/clay/clay/build/_deps"

README.md

@@ -897,18 +897,12 @@ Element is subject to [culling](#visibility-culling). Otherwise, multiple `Clay_
 
 ### CLAY_ID
 
-**Usage**
-
-`CLAY(CLAY_ID(char* idString)) {}`
-
-**Lifecycle**
-
-`Clay_BeginLayout()` -> `CLAY(` -> `CLAY_ID()` -> `)` -> `Clay_EndLayout()` 
-
-**Notes**
+`Clay_ElementId CLAY_ID(STRING_LITERAL idString)`
 
 **CLAY_ID()** is used to generate and attach a [Clay_ElementId](#clay_elementid) to a layout element during declaration.
 
+Note this macro only works with String literals and won't compile if used with a `char*` variable. To use a heap allocated `char*` string as an ID, use [CLAY_SID](#clay_sid). 
+
 To regenerate the same ID outside of layout declaration when using utility functions such as [Clay_PointerOver](#clay_pointerover), use the [Clay_GetElementId](#clay_getelementid) function.
 
 **Examples**
@@ -931,11 +925,31 @@ if (buttonIsHovered && leftMouseButtonPressed) {
 
 ---
 
+### CLAY_SID()
+
+`Clay_ElementId CLAY_SID(Clay_String idString)`
+
+A version of [CLAY_ID](#clay_id) that can be used with heap allocated `char *` data. The underlying `char` data will not be copied internally and should live until at least the next frame.
+
+---
+
 ### CLAY_IDI()
 
-`Clay_ElementId CLAY_IDI(char *label, int32_t index)`
+`Clay_ElementId CLAY_IDI(STRING_LITERAL idString, int32_t index)`
 
-An offset version of [CLAY_ID](#clay_id). Generates a [Clay_ElementId](#clay_elementid) string id from the provided `char *label`, combined with the `int index`. Used for generating ids for sequential elements (such as in a `for` loop) without having to construct dynamic strings at runtime.
+An offset version of [CLAY_ID](#clay_id). Generates a [Clay_ElementId](#clay_elementid) string id from the provided `char *label`, combined with the `int index`.
+
+Used for generating ids for sequential elements (such as in a `for` loop) without having to construct dynamic strings at runtime.
+
+Note this macro only works with String literals and won't compile if used with a `char*` variable. To use a heap allocated `char*` string as an ID, use [CLAY_SIDI](#clay_sidi).
+
+---
+
+### CLAY_SIDI()
+
+`Clay_ElementId CLAY_SIDI(Clay_String idString, int32_t index)`
+
+A version of [CLAY_IDI](#clay_idi) that can be used with heap allocated `char *` data. The underlying `char` data will not be copied internally and should live until at least the next frame.
 
 ---
 
@@ -943,7 +957,7 @@ An offset version of [CLAY_ID](#clay_id). Generates a [Clay_ElementId](#clay_ele
 
 **Usage**
 
-`CLAY(CLAY_ID_LOCAL(char* idString)) {}`
+`Clay_ElementId CLAY_ID_LOCAL(STRING_LITERAL idString)`
 
 **Lifecycle**
 
@@ -957,6 +971,8 @@ Unlike [CLAY_ID](#clay_id) which needs to be globally unique, a local ID is base
 
 As a result, local id is suitable for use in reusable components and loops.
 
+Note this macro only works with String literals and won't compile if used with a `char*` variable. To use a heap allocated `char*` string as an ID, use [CLAY_SID_LOCAL](#clay_sid_local).
+
 **Examples**
 
 ```C
@@ -976,11 +992,31 @@ for (int i = 0; i < headerButtons.length; i++) {
 
 ---
 
+### CLAY_SID_LOCAL()
+
+`Clay_ElementId CLAY_SID_LOCAL(Clay_String idString)`
+
+A version of [CLAY_ID_LOCAL](#clay_id_local) that can be used with heap allocated `char *` data. The underlying `char` data will not be copied internally and should live until at least the next frame.
+
+---
+
 ### CLAY_IDI_LOCAL()
 
-`Clay_ElementId CLAY_IDI_LOCAL(char *label, int32_t index)`
+`Clay_ElementId CLAY_IDI_LOCAL(STRING_LITERAL idString, int32_t index)`
 
-An offset version of [CLAY_ID_LOCAL](#clay_local_id). Generates a [Clay_ElementId](#clay_elementid) string id from the provided `char *label`, combined with the `int index`. Used for generating ids for sequential elements (such as in a `for` loop) without having to construct dynamic strings at runtime.
+An offset version of [CLAY_ID_LOCAL](#clay_local_id). Generates a [Clay_ElementId](#clay_elementid) string id from the provided `char *label`, combined with the `int index`.
+
+Used for generating ids for sequential elements (such as in a `for` loop) without having to construct dynamic strings at runtime.
+
+Note this macro only works with String literals and won't compile if used with a `char*` variable. To use a heap allocated `char*` string as an ID, use [CLAY_SIDI_LOCAL](#clay_sidi_local).
+
+---
+
+### CLAY_SIDI_LOCAL()
+
+`Clay_ElementId CLAY_SIDI_LOCAL(Clay_String idString, int32_t index)`
+
+A version of [CLAY_IDI_LOCAL](#clay_idi_local) that can be used with heap allocated `char *` data. The underlying `char` data will not be copied internally and should live until at least the next frame.
 
 ---
 

clay.h

@@ -71,13 +71,25 @@
 
 #define CLAY_SIZING_PERCENT(percentOfParent) (CLAY__INIT(Clay_SizingAxis) { .size = { .percent = (percentOfParent) }, .type = CLAY__SIZING_TYPE_PERCENT })
 
+// Note: If a compile error led you here, you might be trying to use CLAY_ID with something other than a string literal. To construct an ID with a dynamic string, use CLAY_SID instead.
 #define CLAY_ID(label) CLAY_IDI(label, 0)
 
-#define CLAY_IDI(label, index) Clay__HashString(CLAY_STRING(label), index, 0)
+#define CLAY_SID(label) CLAY_SIDI(label, 0)
 
+// Note: If a compile error led you here, you might be trying to use CLAY_IDI with something other than a string literal. To construct an ID with a dynamic string, use CLAY_SIDI instead.
+#define CLAY_IDI(label, index) CLAY_SIDI(CLAY_STRING(label), index)
+
+#define CLAY_SIDI(label, index) Clay__HashString(label, index, 0)
+
+// Note: If a compile error led you here, you might be trying to use CLAY_ID_LOCAL with something other than a string literal. To construct an ID with a dynamic string, use CLAY_SID_LOCAL instead.
 #define CLAY_ID_LOCAL(label) CLAY_IDI_LOCAL(label, 0)
 
-#define CLAY_IDI_LOCAL(label, index) Clay__HashString(CLAY_STRING(label), index, Clay__GetParentElementId())
+#define CLAY_SID_LOCAL(label) CLAY_SIDI_LOCAL(label, 0)
+
+// Note: If a compile error led you here, you might be trying to use CLAY_IDI_LOCAL with something other than a string literal. To construct an ID with a dynamic string, use CLAY_SIDI_LOCAL instead.
+#define CLAY_IDI_LOCAL(label, index) CLAY_SIDI_LOCAL(CLAY_STRING(label), index)
+
+#define CLAY_SIDI_LOCAL(label, index) Clay__HashString(label, index, Clay__GetParentElementId())
 
 #define CLAY__STRING_LENGTH(s) ((sizeof(s) / sizeof((s)[0])) - sizeof((s)[0]))
 
@@ -2018,54 +2030,11 @@ void Clay__InitializePersistentMemory(Clay_Context* context) {
     context->arenaResetOffset = arena->nextAllocation;
 }
 
-void Clay__CompressChildrenAlongAxis(bool xAxis, float totalSizeToDistribute, Clay__int32_tArray resizableContainerBuffer) {
-    Clay_Context* context = Clay_GetCurrentContext();
-    Clay__int32_tArray largestContainers = context->openClipElementStack;
+const float CLAY__EPSILON = 0.01;
 
-    while (totalSizeToDistribute > 0.1) {
-        largestContainers.length = 0;
-        float largestSize = 0;
-        float targetSize = 0;
-        for (int32_t i = 0; i < resizableContainerBuffer.length; ++i) {
-            Clay_LayoutElement *childElement = Clay_LayoutElementArray_Get(&context->layoutElements, Clay__int32_tArray_GetValue(&resizableContainerBuffer, i));
-            float childSize = xAxis ? childElement->dimensions.width : childElement->dimensions.height;
-            if ((childSize - largestSize) < 0.1 && (childSize - largestSize) > -0.1) {
-                Clay__int32_tArray_Add(&largestContainers, Clay__int32_tArray_GetValue(&resizableContainerBuffer, i));
-            } else if (childSize > largestSize) {
-                targetSize = largestSize;
-                largestSize = childSize;
-                largestContainers.length = 0;
-                Clay__int32_tArray_Add(&largestContainers, Clay__int32_tArray_GetValue(&resizableContainerBuffer, i));
-            }
-            else if (childSize > targetSize) {
-                targetSize = childSize;
-            }
-        }
-
-        if (largestContainers.length == 0) {
-            return;
-        }
-
-        targetSize = CLAY__MAX(targetSize, (largestSize * largestContainers.length) - totalSizeToDistribute) / largestContainers.length;
-
-        for (int32_t childOffset = 0; childOffset < largestContainers.length; childOffset++) {
-            int32_t childIndex = Clay__int32_tArray_GetValue(&largestContainers, childOffset);
-            Clay_LayoutElement *childElement = Clay_LayoutElementArray_Get(&context->layoutElements, childIndex);
-            float *childSize = xAxis ? &childElement->dimensions.width : &childElement->dimensions.height;
-            float childMinSize = xAxis ? childElement->minDimensions.width : childElement->minDimensions.height;
-            float oldChildSize = *childSize;
-            *childSize = CLAY__MAX(childMinSize, targetSize);
-            totalSizeToDistribute -= (oldChildSize - *childSize);
-            if (*childSize == childMinSize) {
-                for (int32_t i = 0; i < resizableContainerBuffer.length; i++) {
-                    if (Clay__int32_tArray_GetValue(&resizableContainerBuffer, i) == childIndex) {
-                        Clay__int32_tArray_RemoveSwapback(&resizableContainerBuffer, i);
-                        break;
-                    }
-                }
-            }
-        }
-    }
+bool Clay__FloatEqual(float left, float right) {
+    float subtracted = left - right;
+    return subtracted < CLAY__EPSILON && subtracted > -CLAY__EPSILON;
 }
 
 void Clay__SizeContainersAlongAxis(bool xAxis) {
@@ -2103,7 +2072,7 @@ void Clay__SizeContainersAlongAxis(bool xAxis) {
             int32_t growContainerCount = 0;
             float parentSize = xAxis ? parent->dimensions.width : parent->dimensions.height;
             float parentPadding = (float)(xAxis ? (parent->layoutConfig->padding.left + parent->layoutConfig->padding.right) : (parent->layoutConfig->padding.top + parent->layoutConfig->padding.bottom));
-            float innerContentSize = 0, growContainerContentSize = 0, totalPaddingAndChildGaps = parentPadding;
+            float innerContentSize = 0, totalPaddingAndChildGaps = parentPadding;
             bool sizingAlongAxis = (xAxis && parentStyleConfig->layoutDirection == CLAY_LEFT_TO_RIGHT) || (!xAxis && parentStyleConfig->layoutDirection == CLAY_TOP_TO_BOTTOM);
             resizableContainerBuffer.length = 0;
             float parentChildGap = parentStyleConfig->childGap;
@@ -2129,7 +2098,6 @@ void Clay__SizeContainersAlongAxis(bool xAxis) {
                 if (sizingAlongAxis) {
                     innerContentSize += (childSizing.type == CLAY__SIZING_TYPE_PERCENT ? 0 : childSize);
                     if (childSizing.type == CLAY__SIZING_TYPE_GROW) {
-                        growContainerContentSize += childSize;
                         growContainerCount++;
                     }
                     if (childOffset > 0) {
@@ -2168,25 +2136,83 @@ void Clay__SizeContainersAlongAxis(bool xAxis) {
                         }
                     }
                     // Scrolling containers preferentially compress before others
-                    Clay__CompressChildrenAlongAxis(xAxis, -sizeToDistribute, resizableContainerBuffer);
+                    while (sizeToDistribute < -CLAY__EPSILON && resizableContainerBuffer.length > 0) {
+                        float largest = 0;
+                        float secondLargest = 0;
+                        float widthToAdd = sizeToDistribute;
+                        for (int childIndex = 0; childIndex < resizableContainerBuffer.length; childIndex++) {
+                            Clay_LayoutElement *child = Clay_LayoutElementArray_Get(&context->layoutElements, Clay__int32_tArray_GetValue(&resizableContainerBuffer, childIndex));
+                            float childSize = xAxis ? child->dimensions.width : child->dimensions.height;
+                            if (Clay__FloatEqual(childSize, largest)) { continue; }
+                            if (childSize > largest) {
+                                secondLargest = largest;
+                                largest = childSize;
+                            }
+                            if (childSize < largest) {
+                                secondLargest = CLAY__MAX(secondLargest, childSize);
+                                widthToAdd = secondLargest - largest;
+                            }
+                        }
+
+                        widthToAdd = CLAY__MAX(widthToAdd, sizeToDistribute / resizableContainerBuffer.length);
+
+                        for (int childIndex = 0; childIndex < resizableContainerBuffer.length; childIndex++) {
+                            Clay_LayoutElement *child = Clay_LayoutElementArray_Get(&context->layoutElements, Clay__int32_tArray_GetValue(&resizableContainerBuffer, childIndex));
+                            float *childSize = xAxis ? &child->dimensions.width : &child->dimensions.height;
+                            float minSize = xAxis ? child->minDimensions.width : child->minDimensions.height;
+                            float previousWidth = *childSize;
+                            if (Clay__FloatEqual(*childSize, largest)) {
+                                *childSize += widthToAdd;
+                                if (*childSize <= minSize) {
+                                    *childSize = minSize;
+                                    Clay__int32_tArray_RemoveSwapback(&resizableContainerBuffer, childIndex--);
+                                }
+                                sizeToDistribute -= (*childSize - previousWidth);
+                            }
+                        }
+                    }
                 // The content is too small, allow SIZING_GROW containers to expand
                 } else if (sizeToDistribute > 0 && growContainerCount > 0) {
-                    float targetSize = (sizeToDistribute + growContainerContentSize) / (float)growContainerCount;
-                    for (int32_t childOffset = 0; childOffset < resizableContainerBuffer.length; childOffset++) {
-                        Clay_LayoutElement *childElement = Clay_LayoutElementArray_Get(&context->layoutElements, Clay__int32_tArray_GetValue(&resizableContainerBuffer, childOffset));
-                        Clay_SizingAxis childSizing = xAxis ? childElement->layoutConfig->sizing.width : childElement->layoutConfig->sizing.height;
-                        if (childSizing.type == CLAY__SIZING_TYPE_GROW) {
-                            float *childSize = xAxis ? &childElement->dimensions.width : &childElement->dimensions.height;
-                            float *minSize = xAxis ? &childElement->minDimensions.width : &childElement->minDimensions.height;
-                            if (targetSize < *minSize) {
-                                growContainerContentSize -= *minSize;
-                                Clay__int32_tArray_RemoveSwapback(&resizableContainerBuffer, childOffset);
-                                growContainerCount--;
-                                targetSize = (sizeToDistribute + growContainerContentSize) / (float)growContainerCount;
-                                childOffset = -1;
-                                continue;
+                    for (int childIndex = 0; childIndex < resizableContainerBuffer.length; childIndex++) {
+                        Clay_LayoutElement *child = Clay_LayoutElementArray_Get(&context->layoutElements, Clay__int32_tArray_GetValue(&resizableContainerBuffer, childIndex));
+                        Clay__SizingType childSizing = xAxis ? child->layoutConfig->sizing.width.type : child->layoutConfig->sizing.height.type;
+                        if (childSizing != CLAY__SIZING_TYPE_GROW) {
+                            Clay__int32_tArray_RemoveSwapback(&resizableContainerBuffer, childIndex--);
+                        }
+                    }
+                    while (sizeToDistribute > CLAY__EPSILON && resizableContainerBuffer.length > 0) {
+                        float smallest = CLAY__MAXFLOAT;
+                        float secondSmallest = CLAY__MAXFLOAT;
+                        float widthToAdd = sizeToDistribute;
+                        for (int childIndex = 0; childIndex < resizableContainerBuffer.length; childIndex++) {
+                            Clay_LayoutElement *child = Clay_LayoutElementArray_Get(&context->layoutElements, Clay__int32_tArray_GetValue(&resizableContainerBuffer, childIndex));
+                            float childSize = xAxis ? child->dimensions.width : child->dimensions.height;
+                            if (Clay__FloatEqual(childSize, smallest)) { continue; }
+                            if (childSize < smallest) {
+                                secondSmallest = smallest;
+                                smallest = childSize;
+                            }
+                            if (childSize > smallest) {
+                                secondSmallest = CLAY__MIN(secondSmallest, childSize);
+                                widthToAdd = secondSmallest - smallest;
+                            }
+                        }
+
+                        widthToAdd = CLAY__MIN(widthToAdd, sizeToDistribute / resizableContainerBuffer.length);
+
+                        for (int childIndex = 0; childIndex < resizableContainerBuffer.length; childIndex++) {
+                            Clay_LayoutElement *child = Clay_LayoutElementArray_Get(&context->layoutElements, Clay__int32_tArray_GetValue(&resizableContainerBuffer, childIndex));
+                            float *childSize = xAxis ? &child->dimensions.width : &child->dimensions.height;
+                            float maxSize = xAxis ? child->layoutConfig->sizing.width.size.minMax.max : child->layoutConfig->sizing.height.size.minMax.max;
+                            float previousWidth = *childSize;
+                            if (Clay__FloatEqual(*childSize, smallest)) {
+                                *childSize += widthToAdd;
+                                if (*childSize >= maxSize) {
+                                    *childSize = maxSize;
+                                    Clay__int32_tArray_RemoveSwapback(&resizableContainerBuffer, childIndex--);
+                                }
+                                sizeToDistribute -= (*childSize - previousWidth);
                             }
-                            *childSize = targetSize;
                         }
                     }
                 }