Add floor, round and ceil

src/ol/style/expressions.js

@@ -38,6 +38,9 @@ import {log2} from '../math.js';
  *   * `['%', value1, value2]` returns the result of `value1 % value2` (modulo)
  *   * `['^', value1, value2]` returns the value of `value1` raised to the `value2` power
  *   * `['abs', value1]` returns the absolute value of `value1`
+ *   * `['floor', value1]` returns the nearest integer less than or equal to `value1`
+ *   * `['round', value1]` returns the nearest integer to `value1`
+ *   * `['ceil', value1]` returns the nearest integer greater than or equal to `value1`
  *   * `['sin', value1]` returns the sine of `value1`
  *   * `['cos', value1]` returns the cosine of `value1`
  *   * `['atan', value1, value2]` returns `atan2(value1, value2)`. If `value2` is not provided, returns `atan(value1)`
@@ -667,6 +670,39 @@ Operators['abs'] = {
   },
 };
 
+Operators['floor'] = {
+  getReturnType: function (args) {
+    return ValueTypes.NUMBER;
+  },
+  toGlsl: function (context, args) {
+    assertArgsCount(args, 1);
+    assertNumbers(args);
+    return `floor(${expressionToGlsl(context, args[0])})`;
+  },
+};
+
+Operators['round'] = {
+  getReturnType: function (args) {
+    return ValueTypes.NUMBER;
+  },
+  toGlsl: function (context, args) {
+    assertArgsCount(args, 1);
+    assertNumbers(args);
+    return `floor(${expressionToGlsl(context, args[0])} + 0.5)`;
+  },
+};
+
+Operators['ceil'] = {
+  getReturnType: function (args) {
+    return ValueTypes.NUMBER;
+  },
+  toGlsl: function (context, args) {
+    assertArgsCount(args, 1);
+    assertNumbers(args);
+    return `ceil(${expressionToGlsl(context, args[0])})`;
+  },
+};
+
 Operators['sin'] = {
   getReturnType: function (args) {
     return ValueTypes.NUMBER;