Files
orx/orx-shader-phrases/src/main/kotlin/ShaderPreprocessor.kt

65 lines
2.9 KiB
Kotlin

package org.openrndr.extra.shaderphrases
import org.openrndr.draw.codeFromURL
import org.openrndr.extra.shaderphrases.annotations.ShaderPhrases
/**
* Preprocess shader source.
* Looks for "#pragma import" statements and injects found phrases.
* @param source GLSL source code encoded as string
* @return GLSL source code with injected shader phrases
*/
fun preprocessShader(source: String): String {
val lines = source.split("\n")
val processed = lines.mapIndexed { index, it ->
if (it.startsWith("#pragma import")) {
val tokens = it.split(" ")
val full = tokens[2]
val fullTokens = full.split(".")
val fieldName = fullTokens.last().replace(";", "").trim()
val packageClassTokens = fullTokens.dropLast(1)
val packageClass = packageClassTokens.joinToString(".")
try {
/* Note that JVM-style reflection is used here because of short-comings in the Kotlin reflection
library (as of 1.3.61), most notably reflection support for file facades is missing. */
val c = Class.forName(packageClass)
if (c.annotations.any { it.annotationClass == ShaderPhrases::class }) {
if (fieldName == "*") {
c.declaredMethods.filter { it.returnType.name == "java.lang.String" }.map {
"/* imported from $packageClass.$it */\n${it.invoke(null)}\n"
}.joinToString("\n") +
c.declaredFields.filter { it.type.name == "java.lang.String" }.map {
"/* imported from $packageClass.$it */\n${it.get(null)}\n"
}.joinToString("\n")
} else {
// TODO add method based phrase resolver like in the wildcard case above.
try {
c.getDeclaredField(fieldName).get(null)
} catch (e: NoSuchFieldException) {
error("field \"$fieldName\" not found in \"#pragma import $packageClass.$fieldName\" on line ${index + 1}")
}
}
} else {
throw IllegalArgumentException("class $packageClass has no ShaderPhrases annotation")
}
} catch (e: ClassNotFoundException) {
error("class \"$packageClass\" not found in \"#pragma import $packageClass\" on line ${index + 1}")
}
} else {
it
}
}
return processed.joinToString("\n")
}
/**
* Preprocess shader source from url
* Looks for "#pragma import" statements and injects found phrases.
* @param url url pointing to GLSL shader source
* @return GLSL source code with injected shader phrases
*/
fun preprocessShaderFromUrl(url: String): String {
return preprocessShader(codeFromURL(url))
}