static jlong nativeOpenPageAndGetSize(JNIEnv* env, jclass thiz, jlong documentPtr, jint pageIndex, jobject outSize) { FPDF_DOCUMENT document = reinterpret_cast<FPDF_DOCUMENT>(documentPtr); FPDF_PAGE page = FPDF_LoadPage(document, pageIndex); if (!page) { jniThrowException(env, "java/lang/IllegalStateException", "cannot load page"); return -1; } double width = 0; double height = 0; const int result = FPDF_GetPageSizeByIndex(document, pageIndex, &width, &height); if (!result) { jniThrowException(env, "java/lang/IllegalStateException", "cannot get page size"); return -1; } env->SetIntField(outSize, gPointClassInfo.x, width); env->SetIntField(outSize, gPointClassInfo.y, height); return reinterpret_cast<jlong>(page); }
static void nativeSetTransformAndClip(JNIEnv* env, jclass thiz, jlong documentPtr, jint pageIndex, jlong transformPtr, jint clipLeft, jint clipTop, jint clipRight, jint clipBottom) { FPDF_DOCUMENT document = reinterpret_cast<FPDF_DOCUMENT>(documentPtr); CPDF_Page* page = (CPDF_Page*) FPDF_LoadPage(document, pageIndex); if (!page) { jniThrowException(env, "java/lang/IllegalStateException", "cannot open page"); return; } double width = 0; double height = 0; const int result = FPDF_GetPageSizeByIndex(document, pageIndex, &width, &height); if (!result) { jniThrowException(env, "java/lang/IllegalStateException", "cannot get page size"); return; } CFX_AffineMatrix matrix; SkMatrix* skTransform = reinterpret_cast<SkMatrix*>(transformPtr); SkScalar transformValues[6]; if (!skTransform->asAffine(transformValues)) { jniThrowException(env, "java/lang/IllegalArgumentException", "transform matrix has perspective. Only affine matrices are allowed."); return; } // PDF's coordinate system origin is left-bottom while in graphics it // is the top-left. So, translate the PDF coordinates to ours. matrix.Set(1, 0, 0, -1, 0, page->GetPageHeight()); // Apply the transformation what was created in our coordinates. matrix.Concat(transformValues[SkMatrix::kAScaleX], transformValues[SkMatrix::kASkewY], transformValues[SkMatrix::kASkewX], transformValues[SkMatrix::kAScaleY], transformValues[SkMatrix::kATransX], transformValues[SkMatrix::kATransY]); // Translate the result back to PDF coordinates. matrix.Concat(1, 0, 0, -1, 0, page->GetPageHeight()); FS_MATRIX transform = {matrix.a, matrix.b, matrix.c, matrix.d, matrix.e, matrix.f}; FS_RECTF clip = {(float) clipLeft, (float) clipTop, (float) clipRight, (float) clipBottom}; FPDFPage_TransFormWithClip(page, &transform, &clip); FPDF_ClosePage(page); }